Added "allowConnectionsWithOlderPeerVersions" setting (default: true)

This controls whether to allow connections with peers below minPeerVersion.

If true, we won't sync with them but they can still sync with us, and will show in the peers list. This is the default, which allows older nodes to continue functioning, but prevents them from interfering with the sync behaviour of updated nodes.

If false, sync will be blocked both ways, and they will not appear in the peers list at all.

pom.xml

@@ -3,7 +3,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>1.4.6</version>
+	<version>1.5.1</version>
 	<packaging>jar</packaging>
 	<properties>
 		<skipTests>true</skipTests>

src/main/java/org/qortal/api/resource/CrossChainResource.java

@@ -262,6 +262,7 @@ public class CrossChainResource {
 
 		// We want both a minimum of 5 trades and enough trades to span at least 4 hours
 		int minimumCount = 5;
+		int maximumCount = 10;
 		long minimumPeriod = 4 * 60 * 60 * 1000L; // ms
 		Boolean isFinished = Boolean.TRUE;
 
@@ -276,7 +277,7 @@ public class CrossChainResource {
 				ACCT acct = acctInfo.getValue().get();
 
 				List<ATStateData> atStates = repository.getATRepository().getMatchingFinalATStatesQuorum(codeHash,
-						isFinished, acct.getModeByteOffset(), (long) AcctMode.REDEEMED.value, minimumCount, minimumPeriod);
+						isFinished, acct.getModeByteOffset(), (long) AcctMode.REDEEMED.value, minimumCount, maximumCount, minimumPeriod);
 
 				for (ATStateData atState : atStates) {
 					CrossChainTradeData crossChainTradeData = acct.populateTradeData(repository, atState);

src/main/java/org/qortal/block/Block.java

@@ -176,19 +176,26 @@ public class Block {
 		 * 
 		 *  @return account-level share "bin" from blockchain config, or null if founder / none found
 		 */
-		public AccountLevelShareBin getShareBin() {
+		public AccountLevelShareBin getShareBin(int blockHeight) {
 			if (this.isMinterFounder)
 				return null;
 
 			final int accountLevel = this.mintingAccountData.getLevel();
 			if (accountLevel <= 0)
-					return null;
+				return null; // level 0 isn't included in any share bins
 
-			final AccountLevelShareBin[] shareBinsByLevel = BlockChain.getInstance().getShareBinsByAccountLevel();
+			final BlockChain blockChain = BlockChain.getInstance();
+			final AccountLevelShareBin[] shareBinsByLevel = blockChain.getShareBinsByAccountLevel();
 			if (accountLevel > shareBinsByLevel.length)
 				return null;
 
-			return shareBinsByLevel[accountLevel];
+			if (blockHeight < blockChain.getShareBinFixHeight())
+				// Off-by-one bug still in effect
+				return shareBinsByLevel[accountLevel];
+
+			// level 1 stored at index 0, level 2 stored at index 1, etc.
+			return shareBinsByLevel[accountLevel-1];
+
 		}
 
 		public long distribute(long accountAmount, Map<String, Long> balanceChanges) {
@@ -789,7 +796,9 @@ public class Block {
 		NumberFormat formatter = new DecimalFormat("0.###E0");
 		boolean isLogging = LOGGER.getLevel().isLessSpecificThan(Level.TRACE);
 
+		int blockCount = 0;
 		for (BlockSummaryData blockSummaryData : blockSummaries) {
+			blockCount++;
 			StringBuilder stringBuilder = isLogging ? new StringBuilder(512) : null;
 
 			if (isLogging)
@@ -818,11 +827,11 @@ public class Block {
 			parentHeight = blockSummaryData.getHeight();
 			parentBlockSignature = blockSummaryData.getSignature();
 
-			/* Potential future consensus change: only comparing the same number of blocks.
-			if (parentHeight >= maxHeight)
+			// After this timestamp, we only compare the same number of blocks
+			if (NTP.getTime() >= BlockChain.getInstance().getCalcChainWeightTimestamp() && parentHeight >= maxHeight)
 				break;
-			*/
 		}
+		LOGGER.debug(String.format("Chain weight calculation was based on %d blocks", blockCount));
 
 		return cumulativeWeight;
 	}
@@ -1328,6 +1337,9 @@ public class Block {
 
 		// Give Controller our cached, valid online accounts data (if any) to help reduce CPU load for next block
 		Controller.getInstance().pushLatestBlocksOnlineAccounts(this.cachedValidOnlineAccounts);
+
+		// Log some debugging info relating to the block weight calculation
+		this.logDebugInfo();
 	}
 
 	protected void increaseAccountLevels() throws DataException {
@@ -1509,6 +1521,9 @@ public class Block {
 	public void orphan() throws DataException {
 		LOGGER.trace(() -> String.format("Orphaning block %d", this.blockData.getHeight()));
 
+		// Log some debugging info relating to the block weight calculation
+		this.logDebugInfo();
+
 		// Return AT fees and delete AT states from repository
 		orphanAtFeesAndStates();
 
@@ -1783,7 +1798,7 @@ public class Block {
 			// Find all accounts in share bin. getShareBin() returns null for minter accounts that are also founders, so they are effectively filtered out.
 			AccountLevelShareBin accountLevelShareBin = accountLevelShareBins.get(binIndex);
 			// Object reference compare is OK as all references are read-only from blockchain config.
-			List<ExpandedAccount> binnedAccounts = expandedAccounts.stream().filter(accountInfo -> accountInfo.getShareBin() == accountLevelShareBin).collect(Collectors.toList());
+			List<ExpandedAccount> binnedAccounts = expandedAccounts.stream().filter(accountInfo -> accountInfo.getShareBin(this.blockData.getHeight()) == accountLevelShareBin).collect(Collectors.toList());
 
 			// No online accounts in this bin? Skip to next one
 			if (binnedAccounts.isEmpty())
@@ -1981,4 +1996,37 @@ public class Block {
 		this.repository.getAccountRepository().tidy();
 	}
 
+	private void logDebugInfo() {
+		try {
+			// Avoid calculations if possible. We have to check against INFO here, since Level.isMoreSpecificThan() confusingly uses <= rather than just <
+			if (LOGGER.getLevel().isMoreSpecificThan(Level.INFO))
+				return;
+
+			if (this.repository == null || this.getMinter() == null || this.getBlockData() == null)
+				return;
+
+			int minterLevel = Account.getRewardShareEffectiveMintingLevel(this.repository, this.getMinter().getPublicKey());
+
+			LOGGER.debug(String.format("======= BLOCK %d (%.8s) =======", this.getBlockData().getHeight(), Base58.encode(this.getSignature())));
+			LOGGER.debug(String.format("Timestamp: %d", this.getBlockData().getTimestamp()));
+			LOGGER.debug(String.format("Minter level: %d", minterLevel));
+			LOGGER.debug(String.format("Online accounts: %d", this.getBlockData().getOnlineAccountsCount()));
+
+			BlockSummaryData blockSummaryData = new BlockSummaryData(this.getBlockData());
+			if (this.getParent() == null || this.getParent().getSignature() == null || blockSummaryData == null || minterLevel == 0)
+				return;
+
+			blockSummaryData.setMinterLevel(minterLevel);
+			BigInteger blockWeight = calcBlockWeight(this.getParent().getHeight(), this.getParent().getSignature(), blockSummaryData);
+			BigInteger keyDistance = calcKeyDistance(this.getParent().getHeight(), this.getParent().getSignature(), blockSummaryData.getMinterPublicKey(), blockSummaryData.getMinterLevel());
+			NumberFormat formatter = new DecimalFormat("0.###E0");
+
+			LOGGER.debug(String.format("Key distance: %s", formatter.format(keyDistance)));
+			LOGGER.debug(String.format("Weight: %s", formatter.format(blockWeight)));
+
+		} catch (DataException e) {
+			LOGGER.info(() -> String.format("Unable to log block debugging info: %s", e.getMessage()));
+		}
+	}
+
 }

src/main/java/org/qortal/block/BlockChain.java

@@ -71,7 +71,9 @@ public class BlockChain {
 
 	public enum FeatureTrigger {
 		atFindNextTransactionFix,
-		newBlockSigHeight;
+		newBlockSigHeight,
+		shareBinFix,
+		calcChainWeightTimestamp;
 	}
 
 	/** Map of which blockchain features are enabled when (height/timestamp) */
@@ -381,6 +383,14 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.newBlockSigHeight.name()).intValue();
 	}
 
+	public int getShareBinFixHeight() {
+		return this.featureTriggers.get(FeatureTrigger.shareBinFix.name()).intValue();
+	}
+
+	public long getCalcChainWeightTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.calcChainWeightTimestamp.name()).longValue();
+	}
+
 	// More complex getters for aspects that change by height or timestamp
 
 	public long getRewardAtHeight(int ourHeight) {

src/main/java/org/qortal/controller/Controller.java

@@ -623,6 +623,11 @@ public class Controller extends Thread {
 		return peerChainTipData == null || peerChainTipData.getLastBlockSignature() == null || inferiorChainTips.contains(new ByteArray(peerChainTipData.getLastBlockSignature()));
 	};
 
+	public static final Predicate<Peer> hasOldVersion = peer -> {
+		final String minPeerVersion = Settings.getInstance().getMinPeerVersion();
+		return peer.isAtLeastVersion(minPeerVersion) == false;
+	};
+
 	private void potentiallySynchronize() throws InterruptedException {
 		// Already synchronizing via another thread?
 		if (this.isSynchronizing)
@@ -639,11 +644,15 @@ public class Controller extends Thread {
 		// Disregard peers that don't have a recent block
 		peers.removeIf(hasNoRecentBlock);
 
+		// Disregard peers that are on an old version
+		peers.removeIf(hasOldVersion);
+
 		checkRecoveryModeForPeers(peers);
 		if (recoveryMode) {
 			peers = Network.getInstance().getHandshakedPeers();
 			peers.removeIf(hasOnlyGenesisBlock);
 			peers.removeIf(hasMisbehaved);
+			peers.removeIf(hasOldVersion);
 		}
 
 		// Check we have enough peers to potentially synchronize

src/main/java/org/qortal/controller/Synchronizer.java

@@ -16,6 +16,7 @@ import org.qortal.account.Account;
 import org.qortal.account.PublicKeyAccount;
 import org.qortal.block.Block;
 import org.qortal.block.Block.ValidationResult;
+import org.qortal.block.BlockChain;
 import org.qortal.data.block.BlockData;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.block.CommonBlockData;
@@ -34,8 +35,10 @@ import org.qortal.network.message.Message.MessageType;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.settings.Settings;
 import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
+import org.qortal.utils.NTP;
 
 public class Synchronizer {
 
@@ -55,9 +58,6 @@ public class Synchronizer {
 	/** Maximum number of block signatures we ask from peer in one go */
 	private static final int MAXIMUM_REQUEST_SIZE = 200; // XXX move to Settings?
 
-	/** Number of retry attempts if a peer fails to respond with the requested data */
-	private static final int MAXIMUM_RETRIES = 2; // XXX move to Settings?
-
 
 	private static Synchronizer instance;
 
@@ -120,6 +120,7 @@ public class Synchronizer {
 					// Check if we can use the cached common block data, by comparing the peer's current chain tip against the peer's chain tip when we last found our common block
 					if (peer.canUseCachedCommonBlockData()) {
 						LOGGER.debug(String.format("Skipping peer %s because we already have the latest common block data in our cache. Cached common block sig is %.08s", peer, Base58.encode(peer.getCommonBlockData().getCommonBlockSummary().getSignature())));
+						commonBlocksFound++;
 						continue;
 					}
 
@@ -226,6 +227,10 @@ public class Synchronizer {
 					return peers;
 				}
 
+				// We will switch to a new chain weight consensus algorithm at a hard fork, so determine if this has happened yet
+				boolean usingSameLengthChainWeight = (NTP.getTime() >= BlockChain.getInstance().getCalcChainWeightTimestamp());
+				LOGGER.debug(String.format("Using %s chain weight consensus algorithm", (usingSameLengthChainWeight ? "same-length" : "variable-length")));
+
 				// Retrieve a list of unique common blocks from this list of peers
 				List<BlockSummaryData> commonBlocks = this.uniqueCommonBlocks(peers);
 
@@ -267,7 +272,7 @@ public class Synchronizer {
 
 					// Calculate the length of the shortest peer chain sharing this common block, including our chain
 					final int ourAdditionalBlocksAfterCommonBlock = ourHeight - commonBlockSummary.getHeight();
-					int minChainLength = this.calculateMinChainLength(commonBlockSummary, ourAdditionalBlocksAfterCommonBlock, peersSharingCommonBlock);
+					int minChainLength = this.calculateMinChainLengthOfPeers(peersSharingCommonBlock, commonBlockSummary);
 
 					// Fetch block summaries from each peer
 					for (Peer peer : peersSharingCommonBlock) {
@@ -303,43 +308,51 @@ public class Synchronizer {
 								if (blockSummaries != null) {
 									LOGGER.trace(String.format("Peer %s returned %d block summar%s", peer, blockSummaries.size(), (blockSummaries.size() != 1 ? "ies" : "y")));
 
-									// We need to adjust minChainLength if peers fail to return all expected block summaries
-									if (blockSummaries.size() < summariesRequired) {
+									if (blockSummaries.size() < summariesRequired)
 										// This could mean that the peer has re-orged. But we still have the same common block, so it's safe to proceed with this set of signatures instead.
 										LOGGER.debug(String.format("Peer %s returned %d block summar%s instead of expected %d", peer, blockSummaries.size(), (blockSummaries.size() != 1 ? "ies" : "y"), summariesRequired));
-
-										// Update minChainLength if we have at least 1 block for this peer. If we don't have any blocks, this peer will be excluded from chain weight comparisons later in the process, so we shouldn't update minChainLength
-										if (blockSummaries.size() > 0)
-											minChainLength = blockSummaries.size();
-									}
 								}
 							} else {
 								// There are no block summaries after this common block
 								peer.getCommonBlockData().setBlockSummariesAfterCommonBlock(null);
 							}
 						}
+
+						// Reduce minChainLength if needed. If we don't have any blocks, this peer will be excluded from chain weight comparisons later in the process, so we shouldn't update minChainLength
+						List <BlockSummaryData> peerBlockSummaries = peer.getCommonBlockData().getBlockSummariesAfterCommonBlock();
+						if (peerBlockSummaries != null && peerBlockSummaries.size() > 0)
+							if (peerBlockSummaries.size() < minChainLength)
+								minChainLength = peerBlockSummaries.size();
 					}
 
 					// Fetch our corresponding block summaries. Limit to MAXIMUM_REQUEST_SIZE, in order to make the comparison fairer, as peers have been limited too
 					final int ourSummariesRequired = Math.min(ourAdditionalBlocksAfterCommonBlock, MAXIMUM_REQUEST_SIZE);
 					LOGGER.trace(String.format("About to fetch our block summaries from %d to %d. Our height: %d", commonBlockSummary.getHeight() + 1, commonBlockSummary.getHeight() + ourSummariesRequired, ourHeight));
 					List<BlockSummaryData> ourBlockSummaries = repository.getBlockRepository().getBlockSummaries(commonBlockSummary.getHeight() + 1, commonBlockSummary.getHeight() + ourSummariesRequired);
-					if (ourBlockSummaries.isEmpty())
+					if (ourBlockSummaries.isEmpty()) {
 						LOGGER.debug(String.format("We don't have any block summaries so can't compare our chain against peers with this common block. We can still compare them against each other."));
-					else
+					}
+					else {
 						populateBlockSummariesMinterLevels(repository, ourBlockSummaries);
+						// Reduce minChainLength if we have less summaries
+						if (ourBlockSummaries.size() < minChainLength)
+							minChainLength = ourBlockSummaries.size();
+					}
 
 					// Create array to hold peers for comparison
 					List<Peer> superiorPeersForComparison = new ArrayList<>();
 
+					// Calculate max height for chain weight comparisons
+					int maxHeightForChainWeightComparisons = commonBlockSummary.getHeight() + minChainLength;
+
 					// Calculate our chain weight
 					BigInteger ourChainWeight = BigInteger.valueOf(0);
 					if (ourBlockSummaries.size() > 0)
-						ourChainWeight = Block.calcChainWeight(commonBlockSummary.getHeight(), commonBlockSummary.getSignature(), ourBlockSummaries, minChainLength);
+						ourChainWeight = Block.calcChainWeight(commonBlockSummary.getHeight(), commonBlockSummary.getSignature(), ourBlockSummaries, maxHeightForChainWeightComparisons);
 
 					NumberFormat formatter = new DecimalFormat("0.###E0");
 					NumberFormat accurateFormatter = new DecimalFormat("0.################E0");
-					LOGGER.debug(String.format("Our chain weight based on %d blocks is %s", ourBlockSummaries.size(), formatter.format(ourChainWeight)));
+					LOGGER.debug(String.format("Our chain weight based on %d blocks is %s", (usingSameLengthChainWeight ? minChainLength : ourBlockSummaries.size()), formatter.format(ourChainWeight)));
 
 					LOGGER.debug(String.format("Listing peers with common block %.8s...", Base58.encode(commonBlockSummary.getSignature())));
 					for (Peer peer : peersSharingCommonBlock) {
@@ -358,10 +371,10 @@ public class Synchronizer {
 						populateBlockSummariesMinterLevels(repository, peerBlockSummariesAfterCommonBlock);
 
 						// Calculate cumulative chain weight of this blockchain subset, from common block to highest mutual block held by all peers in this group.
-						LOGGER.debug(String.format("About to calculate chain weight based on %d blocks for peer %s with common block %.8s (peer has %d blocks after common block)", peerBlockSummariesAfterCommonBlock.size(), peer, Base58.encode(commonBlockSummary.getSignature()), peerAdditionalBlocksAfterCommonBlock));
-						BigInteger peerChainWeight = Block.calcChainWeight(commonBlockSummary.getHeight(), commonBlockSummary.getSignature(), peerBlockSummariesAfterCommonBlock, minChainLength);
+						LOGGER.debug(String.format("About to calculate chain weight based on %d blocks for peer %s with common block %.8s (peer has %d blocks after common block)", (usingSameLengthChainWeight ? minChainLength : peerBlockSummariesAfterCommonBlock.size()), peer, Base58.encode(commonBlockSummary.getSignature()), peerAdditionalBlocksAfterCommonBlock));
+						BigInteger peerChainWeight = Block.calcChainWeight(commonBlockSummary.getHeight(), commonBlockSummary.getSignature(), peerBlockSummariesAfterCommonBlock, maxHeightForChainWeightComparisons);
 						peer.getCommonBlockData().setChainWeight(peerChainWeight);
-						LOGGER.debug(String.format("Chain weight of peer %s based on %d blocks (%d - %d) is %s", peer, peerBlockSummariesAfterCommonBlock.size(), peerBlockSummariesAfterCommonBlock.get(0).getHeight(), peerBlockSummariesAfterCommonBlock.get(peerBlockSummariesAfterCommonBlock.size()-1).getHeight(), formatter.format(peerChainWeight)));
+						LOGGER.debug(String.format("Chain weight of peer %s based on %d blocks (%d - %d) is %s", peer, (usingSameLengthChainWeight ? minChainLength : peerBlockSummariesAfterCommonBlock.size()), peerBlockSummariesAfterCommonBlock.get(0).getHeight(), peerBlockSummariesAfterCommonBlock.get(peerBlockSummariesAfterCommonBlock.size()-1).getHeight(), formatter.format(peerChainWeight)));
 
 						// Compare against our chain - if our blockchain has greater weight then don't synchronize with peer (or any others in this group)
 						if (ourChainWeight.compareTo(peerChainWeight) > 0) {
@@ -425,14 +438,14 @@ public class Synchronizer {
 		return commonBlocks;
 	}
 
-	private int calculateMinChainLength(BlockSummaryData commonBlockSummary, int ourAdditionalBlocksAfterCommonBlock, List<Peer> peersSharingCommonBlock) {
-		// Calculate the length of the shortest peer chain sharing this common block, including our chain
-		int minChainLength = ourAdditionalBlocksAfterCommonBlock;
+	private int calculateMinChainLengthOfPeers(List<Peer> peersSharingCommonBlock, BlockSummaryData commonBlockSummary) {
+		// Calculate the length of the shortest peer chain sharing this common block
+		int minChainLength = 0;
 		for (Peer peer : peersSharingCommonBlock) {
 			final int peerHeight = peer.getChainTipData().getLastHeight();
 			final int peerAdditionalBlocksAfterCommonBlock = peerHeight - commonBlockSummary.getHeight();
 
-			if (peerAdditionalBlocksAfterCommonBlock < minChainLength)
+			if (peerAdditionalBlocksAfterCommonBlock < minChainLength || minChainLength == 0)
 				minChainLength = peerAdditionalBlocksAfterCommonBlock;
 		}
 		return minChainLength;
@@ -703,7 +716,7 @@ public class Synchronizer {
 			populateBlockSummariesMinterLevels(repository, ourBlockSummaries);
 			populateBlockSummariesMinterLevels(repository, peerBlockSummaries);
 
-			final int mutualHeight = commonBlockHeight - 1 + Math.min(ourBlockSummaries.size(), peerBlockSummaries.size());
+			final int mutualHeight = commonBlockHeight + Math.min(ourBlockSummaries.size(), peerBlockSummaries.size());
 
 			// Calculate cumulative chain weights of both blockchain subsets, from common block to highest mutual block.
 			BigInteger ourChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockSig, ourBlockSummaries, mutualHeight);
@@ -733,6 +746,7 @@ public class Synchronizer {
 
 		LOGGER.debug(() -> String.format("Fetching peer %s chain from height %d, sig %.8s", peer, commonBlockHeight, commonBlockSig58));
 
+		final int maxRetries = Settings.getInstance().getMaxRetries();
 
 		// Overall plan: fetch peer's blocks first, then orphan, then apply
 
@@ -771,14 +785,32 @@ public class Synchronizer {
 					if (cachedCommonBlockData != null)
 						cachedCommonBlockData.setBlockSummariesAfterCommonBlock(null);
 
-                    // If we have already received RECENT blocks from this peer, go ahead and apply them
+                    // If we have already received recent or newer blocks from this peer, go ahead and apply them
                     if (peerBlocks.size() > 0) {
+						final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
                     	final Block peerLatestBlock = peerBlocks.get(peerBlocks.size() - 1);
 						final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
-                    	if (peerLatestBlock != null && minLatestBlockTimestamp != null
-								&& peerLatestBlock.getBlockData().getTimestamp() > minLatestBlockTimestamp) {
-							LOGGER.debug("Newly received blocks are recent, so we will apply them");
-							break;
+						if (ourLatestBlockData != null && peerLatestBlock != null && minLatestBlockTimestamp != null) {
+
+							// If we have received at least one recent block, we can apply them
+							if (peerLatestBlock.getBlockData().getTimestamp() > minLatestBlockTimestamp) {
+								LOGGER.debug("Newly received blocks are recent, so we will apply them");
+								break;
+							}
+
+							// If our latest block is very old....
+							if (ourLatestBlockData.getTimestamp() < minLatestBlockTimestamp) {
+								// ... and we have received a block that is more recent than our latest block ...
+								if (peerLatestBlock.getBlockData().getTimestamp() > ourLatestBlockData.getTimestamp()) {
+									// ... then apply the blocks, as it takes us a step forward.
+									// This is particularly useful when starting up a node that was on a small fork when it was last shut down.
+									// In these cases, we now allow the node to sync forward, and get onto the main chain again.
+									// Without this, we would require that the node syncs ENTIRELY with this peer,
+									// and any problems downloading a block would cause all progress to be lost.
+									LOGGER.debug(String.format("Newly received blocks are %d ms newer than our latest block - so we will apply them", peerLatestBlock.getBlockData().getTimestamp() - ourLatestBlockData.getTimestamp()));
+									break;
+								}
+							}
 						}
                     }
                     // Otherwise, give up and move on to the next peer, to avoid putting our chain into an outdated state
@@ -804,16 +836,34 @@ public class Synchronizer {
 				LOGGER.info(String.format("Peer %s failed to respond with block for height %d, sig %.8s", peer,
 						nextHeight, Base58.encode(nextPeerSignature)));
 
-				if (retryCount >= MAXIMUM_RETRIES) {
+				if (retryCount >= maxRetries) {
 
-					// If we have already received RECENT blocks from this peer, go ahead and apply them
+					// If we have already received recent or newer blocks from this peer, go ahead and apply them
 					if (peerBlocks.size() > 0) {
+						final BlockData ourLatestBlockData = repository.getBlockRepository().getLastBlock();
 						final Block peerLatestBlock = peerBlocks.get(peerBlocks.size() - 1);
 						final Long minLatestBlockTimestamp = Controller.getMinimumLatestBlockTimestamp();
-						if (peerLatestBlock != null && minLatestBlockTimestamp != null
-								&& peerLatestBlock.getBlockData().getTimestamp() > minLatestBlockTimestamp) {
-							LOGGER.debug("Newly received blocks are recent, so we will apply them");
-							break;
+						if (ourLatestBlockData != null && peerLatestBlock != null && minLatestBlockTimestamp != null) {
+
+							// If we have received at least one recent block, we can apply them
+							if (peerLatestBlock.getBlockData().getTimestamp() > minLatestBlockTimestamp) {
+								LOGGER.debug("Newly received blocks are recent, so we will apply them");
+								break;
+							}
+
+							// If our latest block is very old....
+							if (ourLatestBlockData.getTimestamp() < minLatestBlockTimestamp) {
+								// ... and we have received a block that is more recent than our latest block ...
+								if (peerLatestBlock.getBlockData().getTimestamp() > ourLatestBlockData.getTimestamp()) {
+									// ... then apply the blocks, as it takes us a step forward.
+									// This is particularly useful when starting up a node that was on a small fork when it was last shut down.
+									// In these cases, we now allow the node to sync forward, and get onto the main chain again.
+									// Without this, we would require that the node syncs ENTIRELY with this peer,
+									// and any problems downloading a block would cause all progress to be lost.
+									LOGGER.debug(String.format("Newly received blocks are %d ms newer than our latest block - so we will apply them", peerLatestBlock.getBlockData().getTimestamp() - ourLatestBlockData.getTimestamp()));
+									break;
+								}
+							}
 						}
 					}
 					// Otherwise, give up and move on to the next peer, to avoid putting our chain into an outdated state
@@ -824,9 +874,9 @@ public class Synchronizer {
 					peerBlockSignatures.clear();
 					numberSignaturesRequired = peerHeight - height;
 
-					// Retry until retryCount reaches MAXIMUM_RETRIES
+					// Retry until retryCount reaches maxRetries
 					retryCount++;
-					int triesRemaining = MAXIMUM_RETRIES - retryCount;
+					int triesRemaining = maxRetries - retryCount;
 					LOGGER.info(String.format("Re-issuing request to peer %s (%d attempt%s remaining)", peer, triesRemaining, (triesRemaining != 1 ? "s" : "")));
 					continue;
 				}

src/main/java/org/qortal/crosschain/Bitcoin.java

@@ -42,35 +42,32 @@ public class Bitcoin extends Bitcoiny {
 			public Collection<ElectrumX.Server> getServers() {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
-						new Server("enode.duckdns.org", Server.ConnectionType.SSL, 50002),
-						new Server("electrumx.ml", Server.ConnectionType.SSL, 50002),
-						new Server("electrum.bitkoins.nl", Server.ConnectionType.SSL, 50512),
-						new Server("btc.electroncash.dk", Server.ConnectionType.SSL, 60002),
-						new Server("electrumx.electricnewyear.net", Server.ConnectionType.SSL, 50002),
-						new Server("dxm.no-ip.biz", Server.ConnectionType.TCP, 50001),
-						new Server("kirsche.emzy.de", Server.ConnectionType.TCP, 50001),
-						new Server("2AZZARITA.hopto.org", Server.ConnectionType.TCP, 50001),
-						new Server("xtrum.com", Server.ConnectionType.TCP, 50001),
-						new Server("electrum.srvmin.network", Server.ConnectionType.TCP, 50001),
-						new Server("electrumx.alexridevski.net", Server.ConnectionType.TCP, 50001),
-						new Server("bitcoin.lukechilds.co", Server.ConnectionType.TCP, 50001),
-						new Server("electrum.poiuty.com", Server.ConnectionType.TCP, 50001),
-						new Server("horsey.cryptocowboys.net", Server.ConnectionType.TCP, 50001),
+						new Server("128.0.190.26", Server.ConnectionType.SSL, 50002),
+						new Server("hodlers.beer", Server.ConnectionType.SSL, 50002),
+						new Server("electrumx.erbium.eu", Server.ConnectionType.TCP, 50001),
+						new Server("electrumx.erbium.eu", Server.ConnectionType.SSL, 50002),
+						new Server("btc.lastingcoin.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.bitaroo.net", Server.ConnectionType.SSL, 50002),
+						new Server("bitcoin.grey.pw", Server.ConnectionType.SSL, 50002),
+						new Server("2electrumx.hopto.me", Server.ConnectionType.SSL, 56022),
+						new Server("185.64.116.15", Server.ConnectionType.SSL, 50002),
+						new Server("kirsche.emzy.de", Server.ConnectionType.SSL, 50002),
+						new Server("alviss.coinjoined.com", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.emzy.de", Server.ConnectionType.SSL, 50002),
 						new Server("electrum.emzy.de", Server.ConnectionType.TCP, 50001),
-						new Server("electrum-server.ninja", Server.ConnectionType.TCP, 50081),
-						new Server("bitcoin.electrumx.multicoin.co", Server.ConnectionType.TCP, 50001),
-						new Server("esx.geekhosters.com", Server.ConnectionType.TCP, 50001),
-						new Server("bitcoin.grey.pw", Server.ConnectionType.TCP, 50003),
-						new Server("exs.ignorelist.com", Server.ConnectionType.TCP, 50001),
-						new Server("electrum.coinext.com.br", Server.ConnectionType.TCP, 50001),
-						new Server("bitcoin.aranguren.org", Server.ConnectionType.TCP, 50001),
-						new Server("skbxmit.coinjoined.com", Server.ConnectionType.TCP, 50001),
-						new Server("alviss.coinjoined.com", Server.ConnectionType.TCP, 50001),
-						new Server("electrum2.privateservers.network", Server.ConnectionType.TCP, 50001),
-						new Server("electrumx.schulzemic.net", Server.ConnectionType.TCP, 50001),
-						new Server("bitcoins.sk", Server.ConnectionType.TCP, 56001),
-						new Server("node.mendonca.xyz", Server.ConnectionType.TCP, 50001),
-						new Server("bitcoin.aranguren.org", Server.ConnectionType.TCP, 50001));
+						new Server("vmd71287.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("btc.litepay.ch", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.stippy.com", Server.ConnectionType.SSL, 50002),
+						new Server("xtrum.com", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.acinq.co", Server.ConnectionType.SSL, 50002),
+						new Server("electrum2.taborsky.cz", Server.ConnectionType.SSL, 50002),
+						new Server("vmd63185.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum2.privateservers.network", Server.ConnectionType.SSL, 50002),
+						new Server("electrumx.alexridevski.net", Server.ConnectionType.SSL, 50002),
+						new Server("192.166.219.200", Server.ConnectionType.SSL, 50002),
+						new Server("2ex.digitaleveryware.com", Server.ConnectionType.SSL, 50002),
+						new Server("dxm.no-ip.biz", Server.ConnectionType.SSL, 50002),
+						new Server("caleb.vegas", Server.ConnectionType.SSL, 50002));
 			}
 
 			@Override
@@ -96,10 +93,8 @@ public class Bitcoin extends Bitcoiny {
 			@Override
 			public Collection<ElectrumX.Server> getServers() {
 				return Arrays.asList(
-						new Server("electrum.blockstream.info", Server.ConnectionType.TCP, 60001),
-						new Server("electrum.blockstream.info", Server.ConnectionType.SSL, 60002),
+						new Server("tn.not.fyi", Server.ConnectionType.SSL, 55002),
 						new Server("electrumx-test.1209k.com", Server.ConnectionType.SSL, 50002),
-						new Server("testnet.qtornado.com", Server.ConnectionType.TCP, 51001),
 						new Server("testnet.qtornado.com", Server.ConnectionType.SSL, 51002),
 						new Server("testnet.aranguren.org", Server.ConnectionType.TCP, 51001),
 						new Server("testnet.aranguren.org", Server.ConnectionType.SSL, 51002),

src/main/java/org/qortal/network/Handshake.java

@@ -4,7 +4,6 @@ import java.util.Arrays;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.regex.Matcher;
-import java.util.regex.Pattern;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -51,7 +50,7 @@ public enum Handshake {
 
 			String versionString = helloMessage.getVersionString();
 
-			Matcher matcher = VERSION_PATTERN.matcher(versionString);
+			Matcher matcher = peer.VERSION_PATTERN.matcher(versionString);
 			if (!matcher.lookingAt()) {
 				LOGGER.debug(() -> String.format("Peer %s sent invalid HELLO version string '%s'", peer, versionString));
 				return null;
@@ -72,6 +71,15 @@ public enum Handshake {
 			peer.setPeersConnectionTimestamp(peersConnectionTimestamp);
 			peer.setPeersVersion(versionString, version);
 
+			if (Settings.getInstance().getAllowConnectionsWithOlderPeerVersions() == false) {
+				// Ensure the peer is running at least the minimum version allowed for connections
+				final String minPeerVersion = Settings.getInstance().getMinPeerVersion();
+				if (peer.isAtLeastVersion(minPeerVersion) == false) {
+					LOGGER.info(String.format("Ignoring peer %s because it is on an old version (%s)", peer, versionString));
+					return null;
+				}
+			}
+
 			return CHALLENGE;
 		}
 
@@ -244,8 +252,6 @@ public enum Handshake {
 	/** Maximum allowed difference between peer's reported timestamp and when they connected, in milliseconds. */
 	private static final long MAX_TIMESTAMP_DELTA = 30 * 1000L; // ms
 
-	private static final Pattern VERSION_PATTERN = Pattern.compile(Controller.VERSION_PREFIX + "(\\d{1,3})\\.(\\d{1,5})\\.(\\d{1,5})");
-
 	private static final long PEER_VERSION_131 = 0x0100030001L;
 
 	private static final int POW_BUFFER_SIZE_PRE_131 = 8 * 1024 * 1024; // bytes

src/main/java/org/qortal/network/Peer.java

@@ -20,9 +20,12 @@ import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.TimeUnit;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.controller.Controller;
 import org.qortal.data.block.CommonBlockData;
 import org.qortal.data.network.PeerChainTipData;
 import org.qortal.data.network.PeerData;
@@ -87,6 +90,9 @@ public class Peer {
 
 	byte[] ourChallenge;
 
+	// Versioning
+	public static final Pattern VERSION_PATTERN = Pattern.compile(Controller.VERSION_PREFIX + "(\\d{1,3})\\.(\\d{1,5})\\.(\\d{1,5})");
+
 	// Peer info
 
 	private final Object peerInfoLock = new Object();
@@ -634,6 +640,35 @@ public class Peer {
 	}
 
 
+	// Minimum version
+
+	public boolean isAtLeastVersion(String minVersionString) {
+		if (minVersionString == null)
+			return false;
+
+		// Add the version prefix
+		minVersionString = Controller.VERSION_PREFIX + minVersionString;
+
+		Matcher matcher = VERSION_PATTERN.matcher(minVersionString);
+		if (!matcher.lookingAt())
+			return false;
+
+		// We're expecting 3 positive shorts, so we can convert 1.2.3 into 0x0100020003
+		long minVersion = 0;
+		for (int g = 1; g <= 3; ++g) {
+			long value = Long.parseLong(matcher.group(g));
+
+			if (value < 0 || value > Short.MAX_VALUE)
+				return false;
+
+			minVersion <<= 16;
+			minVersion |= value;
+		}
+
+		return this.getPeersVersion() >= minVersion;
+	}
+
+
 	// Common block data
 
 	public boolean canUseCachedCommonBlockData() {

src/main/java/org/qortal/repository/ATRepository.java

@@ -98,7 +98,7 @@ public interface ATRepository {
 	 */
 	public List<ATStateData> getMatchingFinalATStatesQuorum(byte[] codeHash, Boolean isFinished,
 			Integer dataByteOffset, Long expectedValue,
-			int minimumCount, long minimumPeriod) throws DataException;
+			int minimumCount, int maximumCount, long minimumPeriod) throws DataException;
 
 	/**
 	 * Returns all ATStateData for a given block height.

src/main/java/org/qortal/repository/hsqldb/HSQLDBATRepository.java

@@ -454,7 +454,7 @@ public class HSQLDBATRepository implements ATRepository {
 	@Override
 	public List<ATStateData> getMatchingFinalATStatesQuorum(byte[] codeHash, Boolean isFinished,
 			Integer dataByteOffset, Long expectedValue,
-			int minimumCount, long minimumPeriod) throws DataException {
+			int minimumCount, int maximumCount, long minimumPeriod) throws DataException {
 		// We need most recent entry first so we can use its timestamp to slice further results
 		List<ATStateData> mostRecentStates = this.getMatchingFinalATStates(codeHash, isFinished,
 				dataByteOffset, expectedValue, null,
@@ -510,7 +510,8 @@ public class HSQLDBATRepository implements ATRepository {
 		bindParams.add(minimumHeight);
 		bindParams.add(minimumCount);
 
-		sql.append("ORDER BY FinalATStates.height DESC");
+		sql.append("ORDER BY FinalATStates.height DESC LIMIT ?");
+		bindParams.add(maximumCount);
 
 		List<ATStateData> atStates = new ArrayList<>();
 

src/main/java/org/qortal/settings/Settings.java

@@ -122,6 +122,15 @@ public class Settings {
 	private int maxNetworkThreadPoolSize = 20;
 	/** Maximum number of threads for network proof-of-work compute, used during handshaking. */
 	private int networkPoWComputePoolSize = 2;
+	/** Maximum number of retry attempts if a peer fails to respond with the requested data */
+	private int maxRetries = 2;
+
+	/** Minimum peer version number required in order to sync with them */
+	private String minPeerVersion = "1.5.0";
+	/** Whether to allow connections with peers below minPeerVersion
+	 * If true, we won't sync with them but they can still sync with us, and will show in the peers list
+	 * If false, sync will be blocked both ways, and they will not appear in the peers list */
+	private boolean allowConnectionsWithOlderPeerVersions = true;
 
 	// Which blockchains this node is running
 	private String blockchainConfig = null; // use default from resources
@@ -408,6 +417,12 @@ public class Settings {
 		return this.networkPoWComputePoolSize;
 	}
 
+	public int getMaxRetries() { return this.maxRetries; }
+
+	public String getMinPeerVersion() { return this.minPeerVersion; }
+
+	public boolean getAllowConnectionsWithOlderPeerVersions() { return this.allowConnectionsWithOlderPeerVersions; }
+
 	public String getBlockchainConfig() {
 		return this.blockchainConfig;
 	}

src/main/resources/blockchain.json

@@ -49,7 +49,9 @@
 	},
 	"featureTriggers": {
 		"atFindNextTransactionFix": 275000,
-		"newBlockSigHeight": 320000
+		"newBlockSigHeight": 320000,
+		"shareBinFix": 399000,
+		"calcChainWeightTimestamp": 1620579600000
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/java/org/qortal/test/ChainWeightTests.java

@@ -3,12 +3,15 @@ package org.qortal.test;
 import static org.junit.Assert.*;
 
 import java.math.BigInteger;
+import java.text.DecimalFormat;
+import java.text.NumberFormat;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Random;
 
 import org.qortal.account.Account;
 import org.qortal.block.Block;
+import org.qortal.block.BlockChain;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
@@ -17,12 +20,21 @@ import org.qortal.test.common.Common;
 import org.qortal.test.common.TestAccount;
 import org.qortal.transform.Transformer;
 import org.qortal.transform.block.BlockTransformer;
+import org.qortal.utils.NTP;
 import org.junit.Before;
+import org.junit.BeforeClass;
 import org.junit.Test;
 
 public class ChainWeightTests extends Common {
 
 	private static final Random RANDOM = new Random();
+	private static final NumberFormat FORMATTER = new DecimalFormat("0.###E0");
+
+	@BeforeClass
+	public static void beforeClass() {
+		// We need this so that NTP.getTime() in Block.calcChainWeight() doesn't return null, causing NPE
+		NTP.setFixedOffset(0L);
+	}
 
 	@Before
 	public void beforeTest() throws DataException {
@@ -89,7 +101,97 @@ public class ChainWeightTests extends Common {
 		}
 	}
 
-	// Check that a longer chain beats a shorter chain
+	// Demonstrates that typical key distance ranges from roughly 1E75 to 1E77
+	@Test
+	public void testKeyDistances() {
+		byte[] parentMinterKey = new byte[Transformer.PUBLIC_KEY_LENGTH];
+		byte[] testKey = new byte[Transformer.PUBLIC_KEY_LENGTH];
+
+		for (int i = 0; i < 50; ++i) {
+			int parentHeight = RANDOM.nextInt(50000);
+			RANDOM.nextBytes(parentMinterKey);
+			RANDOM.nextBytes(testKey);
+			int minterLevel = RANDOM.nextInt(10) + 1;
+
+			BigInteger keyDistance = Block.calcKeyDistance(parentHeight, parentMinterKey, testKey, minterLevel);
+
+			System.out.println(String.format("Parent height: %d, minter level: %d, distance: %s",
+					parentHeight,
+					minterLevel,
+					FORMATTER.format(keyDistance)));
+		}
+	}
+
+	// If typical key distance ranges from 1E75 to 1E77
+	// then we want lots of online accounts to push a 1E75 distance
+	// towards 1E77 so that it competes with a 1E77 key that has hardly any online accounts
+	// 1E75 is approx. 2**249 so maybe that's a good value for Block.ACCOUNTS_COUNT_SHIFT
+	@Test
+	public void testMoreAccountsVersusKeyDistance() throws DataException {
+		BigInteger minimumBetterKeyDistance = BigInteger.TEN.pow(77);
+		BigInteger maximumWorseKeyDistance = BigInteger.TEN.pow(75);
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			final byte[] parentMinterKey = new byte[Transformer.PUBLIC_KEY_LENGTH];
+
+			TestAccount betterAccount = Common.getTestAccount(repository, "bob-reward-share");
+			byte[] betterKey = betterAccount.getPublicKey();
+			int betterMinterLevel = Account.getRewardShareEffectiveMintingLevel(repository, betterKey);
+
+			TestAccount worseAccount = Common.getTestAccount(repository, "dilbert-reward-share");
+			byte[] worseKey = worseAccount.getPublicKey();
+			int worseMinterLevel = Account.getRewardShareEffectiveMintingLevel(repository, worseKey);
+
+			// This is to check that the hard-coded keys ARE actually better/worse as expected, before moving on testing more online accounts
+			BigInteger betterKeyDistance;
+			BigInteger worseKeyDistance;
+
+			int parentHeight = 0;
+			do {
+				++parentHeight;
+				betterKeyDistance = Block.calcKeyDistance(parentHeight, parentMinterKey, betterKey, betterMinterLevel);
+				worseKeyDistance = Block.calcKeyDistance(parentHeight, parentMinterKey, worseKey, worseMinterLevel);
+			} while (betterKeyDistance.compareTo(minimumBetterKeyDistance) < 0 || worseKeyDistance.compareTo(maximumWorseKeyDistance) > 0);
+
+			System.out.println(String.format("Parent height: %d, better key distance: %s, worse key distance: %s",
+					parentHeight,
+					FORMATTER.format(betterKeyDistance),
+					FORMATTER.format(worseKeyDistance)));
+
+			for (int accountsCountShift = 244; accountsCountShift <= 256; accountsCountShift += 2) {
+				for (int worseAccountsCount = 1; worseAccountsCount <= 101; worseAccountsCount += 25) {
+					for (int betterAccountsCount = 1; betterAccountsCount <= 1001; betterAccountsCount += 250) {
+						BlockSummaryData worseKeyBlockSummary = new BlockSummaryData(parentHeight + 1, null, worseKey, betterAccountsCount);
+						BlockSummaryData betterKeyBlockSummary = new BlockSummaryData(parentHeight + 1, null, betterKey, worseAccountsCount);
+
+						populateBlockSummaryMinterLevel(repository, worseKeyBlockSummary);
+						populateBlockSummaryMinterLevel(repository, betterKeyBlockSummary);
+
+						BigInteger worseKeyBlockWeight = calcBlockWeight(parentHeight, parentMinterKey, worseKeyBlockSummary, accountsCountShift);
+						BigInteger betterKeyBlockWeight = calcBlockWeight(parentHeight, parentMinterKey, betterKeyBlockSummary, accountsCountShift);
+
+						System.out.println(String.format("Shift: %d, worse key: %d accounts, %s diff; better key: %d accounts: %s diff; winner: %s",
+								accountsCountShift,
+								betterAccountsCount, // used with worseKey
+								FORMATTER.format(worseKeyBlockWeight),
+								worseAccountsCount, // used with betterKey
+								FORMATTER.format(betterKeyBlockWeight),
+								worseKeyBlockWeight.compareTo(betterKeyBlockWeight) > 0 ? "worse key/better accounts" : "better key/worse accounts"
+								));
+					}
+				}
+
+				System.out.println();
+			}
+		}
+	}
+
+	private static BigInteger calcBlockWeight(int parentHeight, byte[] parentBlockSignature, BlockSummaryData blockSummaryData, int accountsCountShift) {
+		BigInteger keyDistance = Block.calcKeyDistance(parentHeight, parentBlockSignature, blockSummaryData.getMinterPublicKey(), blockSummaryData.getMinterLevel());
+		return BigInteger.valueOf(blockSummaryData.getOnlineAccountsCount()).shiftLeft(accountsCountShift).add(keyDistance);
+	}
+
+	// Check that a longer chain has same weight as shorter/truncated chain
 	@Test
 	public void testLongerChain() throws DataException {
 		try (final Repository repository = RepositoryManager.getRepository()) {
@@ -97,18 +199,20 @@ public class ChainWeightTests extends Common {
 			BlockSummaryData commonBlockSummary = genBlockSummary(repository, commonBlockHeight);
 			byte[] commonBlockGeneratorKey = commonBlockSummary.getMinterPublicKey();
 
-			List<BlockSummaryData> shorterChain = genBlockSummaries(repository, 3, commonBlockSummary);
-			List<BlockSummaryData> longerChain = genBlockSummaries(repository, shorterChain.size() + 1, commonBlockSummary);
-
-			populateBlockSummariesMinterLevels(repository, shorterChain);
+			List<BlockSummaryData> longerChain = genBlockSummaries(repository, 6, commonBlockSummary);
 			populateBlockSummariesMinterLevels(repository, longerChain);
 
+			List<BlockSummaryData> shorterChain = longerChain.subList(0, longerChain.size() / 2);
+
 			final int mutualHeight = commonBlockHeight - 1 + Math.min(shorterChain.size(), longerChain.size());
 
 			BigInteger shorterChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockGeneratorKey, shorterChain, mutualHeight);
 			BigInteger longerChainWeight = Block.calcChainWeight(commonBlockHeight, commonBlockGeneratorKey, longerChain, mutualHeight);
 
-			assertEquals("longer chain should have greater weight", 1, longerChainWeight.compareTo(shorterChainWeight));
+			if (NTP.getTime() >= BlockChain.getInstance().getCalcChainWeightTimestamp())
+				assertEquals("longer chain should have same weight", 0, longerChainWeight.compareTo(shorterChainWeight));
+			else
+				assertEquals("longer chain should have greater weight", 1, longerChainWeight.compareTo(shorterChainWeight));
 		}
 	}
 

src/test/java/org/qortal/test/minting/RewardTests.java

@@ -336,4 +336,457 @@ public class RewardTests extends Common {
 		}
 	}
 
+	/** Test rewards for level 1 and 2 accounts both pre and post the shareBinFix, including orphaning back through the feature trigger block */
+	@Test
+	public void testLevel1And2Rewards() throws DataException {
+		Common.useSettings("test-settings-v2-reward-levels.json");
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<PrivateKeyAccount> mintingAndOnlineAccounts = new ArrayList<>();
+
+			// Alice self share online
+			PrivateKeyAccount aliceSelfShare = Common.getTestAccount(repository, "alice-reward-share");
+			mintingAndOnlineAccounts.add(aliceSelfShare);
+
+			// Bob self-share NOT online
+
+			// Chloe self share online
+			byte[] chloeRewardSharePrivateKey = AccountUtils.rewardShare(repository, "chloe", "chloe", 0);
+			PrivateKeyAccount chloeRewardShareAccount = new PrivateKeyAccount(repository, chloeRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(chloeRewardShareAccount);
+
+			// Dilbert self share online
+			byte[] dilbertRewardSharePrivateKey = AccountUtils.rewardShare(repository, "dilbert", "dilbert", 0);
+			PrivateKeyAccount dilbertRewardShareAccount = new PrivateKeyAccount(repository, dilbertRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(dilbertRewardShareAccount);
+
+			// Mint a couple of blocks so that we are able to orphan them later
+			for (int i=0; i<2; i++)
+				BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure that the levels are as we expect
+			assertEquals(1, (int) Common.getTestAccount(repository, "alice").getLevel());
+			assertEquals(1, (int) Common.getTestAccount(repository, "bob").getLevel());
+			assertEquals(1, (int) Common.getTestAccount(repository, "chloe").getLevel());
+			assertEquals(2, (int) Common.getTestAccount(repository, "dilbert").getLevel());
+
+			// Ensure that only Alice is a founder
+			assertEquals(1, getFlags(repository, "alice"));
+			assertEquals(0, getFlags(repository, "bob"));
+			assertEquals(0, getFlags(repository, "chloe"));
+			assertEquals(0, getFlags(repository, "dilbert"));
+
+			// Now that everyone is at level 1 or 2, we can capture initial balances
+			Map<String, Map<Long, Long>> initialBalances = AccountUtils.getBalances(repository, Asset.QORT, Asset.LEGACY_QORA, Asset.QORT_FROM_QORA);
+			final long aliceInitialBalance = initialBalances.get("alice").get(Asset.QORT);
+			final long bobInitialBalance = initialBalances.get("bob").get(Asset.QORT);
+			final long chloeInitialBalance = initialBalances.get("chloe").get(Asset.QORT);
+			final long dilbertInitialBalance = initialBalances.get("dilbert").get(Asset.QORT);
+
+			// Mint a block
+			final long blockReward = BlockUtils.getNextBlockReward(repository);
+			BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure we are at the correct height and block reward value
+			assertEquals(6, (int) repository.getBlockRepository().getLastBlock().getHeight());
+			assertEquals(10000000000L, blockReward);
+
+			/*
+			 * Alice, Chloe, and Dilbert are 'online'. Bob is offline.
+			 * Chloe is level 1, Dilbert is level 2.
+			 * One founder online (Alice, who is also level 1).
+			 * No legacy QORA holders.
+			 *
+			 * Chloe and Dilbert should receive equal shares of the 5% block reward for Level 1 and 2
+			 * Alice should receive the remainder (95%)
+			 */
+
+			// We are after the shareBinFix feature trigger, so we expect level 1 and 2 to share the same reward (5%)
+			final int level1And2SharePercent = 5_00; // 5%
+			final long level1And2ShareAmount = (blockReward * level1And2SharePercent) / 100L / 100L;
+			final long expectedReward = level1And2ShareAmount / 2; // The reward is split between Chloe and Dilbert
+			final long expectedFounderReward = blockReward - level1And2ShareAmount; // Alice should receive the remainder
+
+			// Validate the balances to ensure that the correct post-shareBinFix distribution is being applied
+			assertEquals(500000000, level1And2ShareAmount);
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance+expectedFounderReward);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance); // Bob not online so his balance remains the same
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance+expectedReward);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance+expectedReward);
+
+			// Now orphan the latest block. This brings us to the threshold of the shareBinFix feature trigger.
+			BlockUtils.orphanBlocks(repository, 1);
+			assertEquals(5, (int) repository.getBlockRepository().getLastBlock().getHeight());
+
+			// Ensure the latest post-fix block rewards have been subtracted and they have returned to their initial values
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance); // Bob not online so his balance remains the same
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance);
+
+			// Orphan another block. This time, the block that was orphaned was prior to the shareBinFix feature trigger.
+			BlockUtils.orphanBlocks(repository, 1);
+			assertEquals(4, (int) repository.getBlockRepository().getLastBlock().getHeight());
+
+			// Prior to the fix, the levels were incorrectly grouped
+			// Chloe should receive 100% of the level 1 reward, and Dilbert should receive 100% of the level 2+3 reward
+			final int level1SharePercent = 5_00; // 5%
+			final int level2And3SharePercent = 10_00; // 10%
+			final long level1ShareAmountBeforeFix = (blockReward * level1SharePercent) / 100L / 100L;
+			final long level2And3ShareAmountBeforeFix = (blockReward * level2And3SharePercent) / 100L / 100L;
+			final long expectedFounderRewardBeforeFix = blockReward - level1ShareAmountBeforeFix - level2And3ShareAmountBeforeFix; // Alice should receive the remainder
+
+			// Validate the share amounts and balances
+			assertEquals(500000000, level1ShareAmountBeforeFix);
+			assertEquals(1000000000, level2And3ShareAmountBeforeFix);
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance-expectedFounderRewardBeforeFix);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance); // Bob not online so his balance remains the same
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance-level1ShareAmountBeforeFix);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance-level2And3ShareAmountBeforeFix);
+
+			// Orphan the latest block one last time
+			BlockUtils.orphanBlocks(repository, 1);
+			assertEquals(3, (int) repository.getBlockRepository().getLastBlock().getHeight());
+
+			// Validate balances
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance-(expectedFounderRewardBeforeFix*2));
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance); // Bob not online so his balance remains the same
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance-(level1ShareAmountBeforeFix*2));
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance-(level2And3ShareAmountBeforeFix*2));
+
+		}
+	}
+
+	/** Test rewards for level 3 and 4 accounts */
+	@Test
+	public void testLevel3And4Rewards() throws DataException {
+		Common.useSettings("test-settings-v2-reward-levels.json");
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+			List<PrivateKeyAccount> mintingAndOnlineAccounts = new ArrayList<>();
+
+			// Alice self share online
+			PrivateKeyAccount aliceSelfShare = Common.getTestAccount(repository, "alice-reward-share");
+			mintingAndOnlineAccounts.add(aliceSelfShare);
+
+			// Bob self-share online
+			byte[] bobRewardSharePrivateKey = AccountUtils.rewardShare(repository, "bob", "bob", 0);
+			PrivateKeyAccount bobRewardShareAccount = new PrivateKeyAccount(repository, bobRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(bobRewardShareAccount);
+
+			// Chloe self share online
+			byte[] chloeRewardSharePrivateKey = AccountUtils.rewardShare(repository, "chloe", "chloe", 0);
+			PrivateKeyAccount chloeRewardShareAccount = new PrivateKeyAccount(repository, chloeRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(chloeRewardShareAccount);
+
+			// Dilbert self share online
+			byte[] dilbertRewardSharePrivateKey = AccountUtils.rewardShare(repository, "dilbert", "dilbert", 0);
+			PrivateKeyAccount dilbertRewardShareAccount = new PrivateKeyAccount(repository, dilbertRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(dilbertRewardShareAccount);
+			
+			// Mint enough blocks to bump testAccount levels to 3 and 4
+			final int minterBlocksNeeded = cumulativeBlocksByLevel.get(4) - 20; // 20 blocks before level 4, so that the test accounts reach the correct levels
+			for (int bc = 0; bc < minterBlocksNeeded; ++bc)
+				BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure that the levels are as we expect
+			assertEquals(3, (int) Common.getTestAccount(repository, "alice").getLevel());
+			assertEquals(3, (int) Common.getTestAccount(repository, "bob").getLevel());
+			assertEquals(3, (int) Common.getTestAccount(repository, "chloe").getLevel());
+			assertEquals(4, (int) Common.getTestAccount(repository, "dilbert").getLevel());
+
+			// Now that everyone is at level 3 or 4, we can capture initial balances
+			Map<String, Map<Long, Long>> initialBalances = AccountUtils.getBalances(repository, Asset.QORT, Asset.LEGACY_QORA, Asset.QORT_FROM_QORA);
+			final long aliceInitialBalance = initialBalances.get("alice").get(Asset.QORT);
+			final long bobInitialBalance = initialBalances.get("bob").get(Asset.QORT);
+			final long chloeInitialBalance = initialBalances.get("chloe").get(Asset.QORT);
+			final long dilbertInitialBalance = initialBalances.get("dilbert").get(Asset.QORT);
+
+			// Mint a block
+			final long blockReward = BlockUtils.getNextBlockReward(repository);
+			BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure we are using the correct block reward value
+			assertEquals(100000000L, blockReward);
+
+			/*
+			 * Alice, Bob, Chloe, and Dilbert are 'online'.
+			 * Bob and Chloe are level 3; Dilbert is level 4.
+			 * One founder online (Alice, who is also level 3).
+			 * No legacy QORA holders.
+			 *
+			 * Chloe, Bob and Dilbert should receive equal shares of the 10% block reward for level 3 and 4
+			 * Alice should receive the remainder (90%)
+			 */
+
+			// We are after the shareBinFix feature trigger, so we expect level 3 and 4 to share the same reward (10%)
+			final int level3And4SharePercent = 10_00; // 10%
+			final long level3And4ShareAmount = (blockReward * level3And4SharePercent) / 100L / 100L;
+			final long expectedReward = level3And4ShareAmount / 3; // The reward is split between Bob, Chloe, and Dilbert
+			final long expectedFounderReward = blockReward - level3And4ShareAmount; // Alice should receive the remainder
+
+			// Validate the balances to ensure that the correct post-shareBinFix distribution is being applied
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance+expectedFounderReward);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance+expectedReward);
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance+expectedReward);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance+expectedReward);
+
+		}
+	}
+
+	/** Test rewards for level 5 and 6 accounts */
+	@Test
+	public void testLevel5And6Rewards() throws DataException {
+		Common.useSettings("test-settings-v2-reward-levels.json");
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+			List<PrivateKeyAccount> mintingAndOnlineAccounts = new ArrayList<>();
+
+			// Alice self share online
+			PrivateKeyAccount aliceSelfShare = Common.getTestAccount(repository, "alice-reward-share");
+			mintingAndOnlineAccounts.add(aliceSelfShare);
+
+			// Bob self-share not initially online
+
+			// Chloe self share online
+			byte[] chloeRewardSharePrivateKey = AccountUtils.rewardShare(repository, "chloe", "chloe", 0);
+			PrivateKeyAccount chloeRewardShareAccount = new PrivateKeyAccount(repository, chloeRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(chloeRewardShareAccount);
+
+			// Dilbert self share online
+			byte[] dilbertRewardSharePrivateKey = AccountUtils.rewardShare(repository, "dilbert", "dilbert", 0);
+			PrivateKeyAccount dilbertRewardShareAccount = new PrivateKeyAccount(repository, dilbertRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(dilbertRewardShareAccount);
+
+			// Mint enough blocks to bump testAccount levels to 5 and 6
+			final int minterBlocksNeeded = cumulativeBlocksByLevel.get(6) - 20; // 20 blocks before level 6, so that the test accounts reach the correct levels
+			for (int bc = 0; bc < minterBlocksNeeded; ++bc)
+				BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Bob self-share now comes online
+			byte[] bobRewardSharePrivateKey = AccountUtils.rewardShare(repository, "bob", "bob", 0);
+			PrivateKeyAccount bobRewardShareAccount = new PrivateKeyAccount(repository, bobRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(bobRewardShareAccount);
+
+			// Ensure that the levels are as we expect
+			assertEquals(5, (int) Common.getTestAccount(repository, "alice").getLevel());
+			assertEquals(1, (int) Common.getTestAccount(repository, "bob").getLevel());
+			assertEquals(5, (int) Common.getTestAccount(repository, "chloe").getLevel());
+			assertEquals(6, (int) Common.getTestAccount(repository, "dilbert").getLevel());
+
+			// Now that everyone is at level 5 or 6 (except Bob who has only just started minting, so is at level 1), we can capture initial balances
+			Map<String, Map<Long, Long>> initialBalances = AccountUtils.getBalances(repository, Asset.QORT, Asset.LEGACY_QORA, Asset.QORT_FROM_QORA);
+			final long aliceInitialBalance = initialBalances.get("alice").get(Asset.QORT);
+			final long bobInitialBalance = initialBalances.get("bob").get(Asset.QORT);
+			final long chloeInitialBalance = initialBalances.get("chloe").get(Asset.QORT);
+			final long dilbertInitialBalance = initialBalances.get("dilbert").get(Asset.QORT);
+
+			// Mint a block
+			final long blockReward = BlockUtils.getNextBlockReward(repository);
+			BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure we are using the correct block reward value
+			assertEquals(100000000L, blockReward);
+
+			/*
+			 * Alice, Bob, Chloe, and Dilbert are 'online'.
+			 * Bob is level 1; Chloe is level 5; Dilbert is level 6.
+			 * One founder online (Alice, who is also level 5).
+			 * No legacy QORA holders.
+			 *
+			 * Chloe and Dilbert should receive equal shares of the 15% block reward for level 5 and 6
+			 * Bob should receive all of the level 1 and 2 reward (5%)
+			 * Alice should receive the remainder (80%)
+			 */
+
+			// We are after the shareBinFix feature trigger, so we expect level 5 and 6 to share the same reward (15%)
+			final int level1And2SharePercent = 5_00; // 5%
+			final int level5And6SharePercent = 15_00; // 10%
+			final long level1And2ShareAmount = (blockReward * level1And2SharePercent) / 100L / 100L;
+			final long level5And6ShareAmount = (blockReward * level5And6SharePercent) / 100L / 100L;
+			final long expectedLevel1And2Reward = level1And2ShareAmount; // The reward is given entirely to Bob
+			final long expectedLevel5And6Reward = level5And6ShareAmount / 2; // The reward is split between Chloe and Dilbert
+			final long expectedFounderReward = blockReward - level1And2ShareAmount - level5And6ShareAmount; // Alice should receive the remainder
+
+			// Validate the balances to ensure that the correct post-shareBinFix distribution is being applied
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance+expectedFounderReward);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance+expectedLevel1And2Reward);
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance+expectedLevel5And6Reward);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance+expectedLevel5And6Reward);
+
+		}
+	}
+
+	/** Test rewards for level 7 and 8 accounts */
+	@Test
+	public void testLevel7And8Rewards() throws DataException {
+		Common.useSettings("test-settings-v2-reward-levels.json");
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+			List<PrivateKeyAccount> mintingAndOnlineAccounts = new ArrayList<>();
+
+			// Alice self share online
+			PrivateKeyAccount aliceSelfShare = Common.getTestAccount(repository, "alice-reward-share");
+			mintingAndOnlineAccounts.add(aliceSelfShare);
+
+			// Bob self-share NOT online
+
+			// Chloe self share online
+			byte[] chloeRewardSharePrivateKey = AccountUtils.rewardShare(repository, "chloe", "chloe", 0);
+			PrivateKeyAccount chloeRewardShareAccount = new PrivateKeyAccount(repository, chloeRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(chloeRewardShareAccount);
+
+			// Dilbert self share online
+			byte[] dilbertRewardSharePrivateKey = AccountUtils.rewardShare(repository, "dilbert", "dilbert", 0);
+			PrivateKeyAccount dilbertRewardShareAccount = new PrivateKeyAccount(repository, dilbertRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(dilbertRewardShareAccount);
+
+			// Mint enough blocks to bump testAccount levels to 7 and 8
+			final int minterBlocksNeeded = cumulativeBlocksByLevel.get(8) - 20; // 20 blocks before level 8, so that the test accounts reach the correct levels
+			for (int bc = 0; bc < minterBlocksNeeded; ++bc)
+				BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure that the levels are as we expect
+			assertEquals(7, (int) Common.getTestAccount(repository, "alice").getLevel());
+			assertEquals(1, (int) Common.getTestAccount(repository, "bob").getLevel());
+			assertEquals(7, (int) Common.getTestAccount(repository, "chloe").getLevel());
+			assertEquals(8, (int) Common.getTestAccount(repository, "dilbert").getLevel());
+
+			// Now that everyone is at level 7 or 8 (except Bob who has only just started minting, so is at level 1), we can capture initial balances
+			Map<String, Map<Long, Long>> initialBalances = AccountUtils.getBalances(repository, Asset.QORT, Asset.LEGACY_QORA, Asset.QORT_FROM_QORA);
+			final long aliceInitialBalance = initialBalances.get("alice").get(Asset.QORT);
+			final long bobInitialBalance = initialBalances.get("bob").get(Asset.QORT);
+			final long chloeInitialBalance = initialBalances.get("chloe").get(Asset.QORT);
+			final long dilbertInitialBalance = initialBalances.get("dilbert").get(Asset.QORT);
+
+			// Mint a block
+			final long blockReward = BlockUtils.getNextBlockReward(repository);
+			BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure we are using the correct block reward value
+			assertEquals(100000000L, blockReward);
+
+			/*
+			 * Alice, Chloe, and Dilbert are 'online'.
+			 * Chloe is level 7; Dilbert is level 8.
+			 * One founder online (Alice, who is also level 7).
+			 * No legacy QORA holders.
+			 *
+			 * Chloe and Dilbert should receive equal shares of the 20% block reward for level 7 and 8
+			 * Alice should receive the remainder (80%)
+			 */
+
+			// We are after the shareBinFix feature trigger, so we expect level 7 and 8 to share the same reward (20%)
+			final int level7And8SharePercent = 20_00; // 20%
+			final long level7And8ShareAmount = (blockReward * level7And8SharePercent) / 100L / 100L;
+			final long expectedLevel7And8Reward = level7And8ShareAmount / 2; // The reward is split between Chloe and Dilbert
+			final long expectedFounderReward = blockReward - level7And8ShareAmount; // Alice should receive the remainder
+
+			// Validate the balances to ensure that the correct post-shareBinFix distribution is being applied
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance+expectedFounderReward);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance); // Bob not online so his balance remains the same
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance+expectedLevel7And8Reward);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance+expectedLevel7And8Reward);
+
+		}
+	}
+
+	/** Test rewards for level 9 and 10 accounts */
+	@Test
+	public void testLevel9And10Rewards() throws DataException {
+		Common.useSettings("test-settings-v2-reward-levels.json");
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+
+			List<Integer> cumulativeBlocksByLevel = BlockChain.getInstance().getCumulativeBlocksByLevel();
+			List<PrivateKeyAccount> mintingAndOnlineAccounts = new ArrayList<>();
+
+			// Alice self share online
+			PrivateKeyAccount aliceSelfShare = Common.getTestAccount(repository, "alice-reward-share");
+			mintingAndOnlineAccounts.add(aliceSelfShare);
+
+			// Bob self-share not initially online
+
+			// Chloe self share online
+			byte[] chloeRewardSharePrivateKey = AccountUtils.rewardShare(repository, "chloe", "chloe", 0);
+			PrivateKeyAccount chloeRewardShareAccount = new PrivateKeyAccount(repository, chloeRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(chloeRewardShareAccount);
+
+			// Dilbert self share online
+			byte[] dilbertRewardSharePrivateKey = AccountUtils.rewardShare(repository, "dilbert", "dilbert", 0);
+			PrivateKeyAccount dilbertRewardShareAccount = new PrivateKeyAccount(repository, dilbertRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(dilbertRewardShareAccount);
+
+			// Mint enough blocks to bump testAccount levels to 9 and 10
+			final int minterBlocksNeeded = cumulativeBlocksByLevel.get(10) - 20; // 20 blocks before level 10, so that the test accounts reach the correct levels
+			for (int bc = 0; bc < minterBlocksNeeded; ++bc)
+				BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Bob self-share now comes online
+			byte[] bobRewardSharePrivateKey = AccountUtils.rewardShare(repository, "bob", "bob", 0);
+			PrivateKeyAccount bobRewardShareAccount = new PrivateKeyAccount(repository, bobRewardSharePrivateKey);
+			mintingAndOnlineAccounts.add(bobRewardShareAccount);
+
+			// Ensure that the levels are as we expect
+			assertEquals(9, (int) Common.getTestAccount(repository, "alice").getLevel());
+			assertEquals(1, (int) Common.getTestAccount(repository, "bob").getLevel());
+			assertEquals(9, (int) Common.getTestAccount(repository, "chloe").getLevel());
+			assertEquals(10, (int) Common.getTestAccount(repository, "dilbert").getLevel());
+
+			// Now that everyone is at level 7 or 8 (except Bob who has only just started minting, so is at level 1), we can capture initial balances
+			Map<String, Map<Long, Long>> initialBalances = AccountUtils.getBalances(repository, Asset.QORT, Asset.LEGACY_QORA, Asset.QORT_FROM_QORA);
+			final long aliceInitialBalance = initialBalances.get("alice").get(Asset.QORT);
+			final long bobInitialBalance = initialBalances.get("bob").get(Asset.QORT);
+			final long chloeInitialBalance = initialBalances.get("chloe").get(Asset.QORT);
+			final long dilbertInitialBalance = initialBalances.get("dilbert").get(Asset.QORT);
+
+			// Mint a block
+			final long blockReward = BlockUtils.getNextBlockReward(repository);
+			BlockMinter.mintTestingBlock(repository, mintingAndOnlineAccounts.toArray(new PrivateKeyAccount[0]));
+
+			// Ensure we are using the correct block reward value
+			assertEquals(100000000L, blockReward);
+
+			/*
+			 * Alice, Bob, Chloe, and Dilbert are 'online'.
+			 * Bob is level 1; Chloe is level 9; Dilbert is level 10.
+			 * One founder online (Alice, who is also level 9).
+			 * No legacy QORA holders.
+			 *
+			 * Chloe and Dilbert should receive equal shares of the 25% block reward for level 9 and 10
+			 * Bob should receive all of the level 1 and 2 reward (5%)
+			 * Alice should receive the remainder (70%)
+			 */
+
+			// We are after the shareBinFix feature trigger, so we expect level 9 and 10 to share the same reward (25%)
+			final int level1And2SharePercent = 5_00; // 5%
+			final int level9And10SharePercent = 25_00; // 25%
+			final long level1And2ShareAmount = (blockReward * level1And2SharePercent) / 100L / 100L;
+			final long level9And10ShareAmount = (blockReward * level9And10SharePercent) / 100L / 100L;
+			final long expectedLevel1And2Reward = level1And2ShareAmount; // The reward is given entirely to Bob
+			final long expectedLevel9And10Reward = level9And10ShareAmount / 2; // The reward is split between Chloe and Dilbert
+			final long expectedFounderReward = blockReward - level1And2ShareAmount - level9And10ShareAmount; // Alice should receive the remainder
+
+			// Validate the balances to ensure that the correct post-shareBinFix distribution is being applied
+			AccountUtils.assertBalance(repository, "alice", Asset.QORT, aliceInitialBalance+expectedFounderReward);
+			AccountUtils.assertBalance(repository, "bob", Asset.QORT, bobInitialBalance+expectedLevel1And2Reward);
+			AccountUtils.assertBalance(repository, "chloe", Asset.QORT, chloeInitialBalance+expectedLevel9And10Reward);
+			AccountUtils.assertBalance(repository, "dilbert", Asset.QORT, dilbertInitialBalance+expectedLevel9And10Reward);
+
+		}
+	}
+
+
+	private int getFlags(Repository repository, String name) throws DataException {
+		TestAccount testAccount = Common.getTestAccount(repository, name);
+		return repository.getAccountRepository().getAccount(testAccount.getAddress()).getFlags();
+	}
+
 }

src/test/resources/test-chain-v2-founder-rewards.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2-leftover-reward.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2-minting.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2-qora-holder-extremes.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2-qora-holder.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2-reward-levels.json

@@ -0,0 +1,75 @@
+{
+	"isTestChain": true,
+	"blockTimestampMargin": 500,
+	"transactionExpiryPeriod": 86400000,
+	"maxBlockSize": 2097152,
+	"maxBytesPerUnitFee": 1024,
+	"unitFee": "0.1",
+	"requireGroupForApproval": false,
+	"minAccountLevelToRewardShare": 5,
+	"maxRewardSharesPerMintingAccount": 20,
+	"founderEffectiveMintingLevel": 10,
+	"onlineAccountSignaturesMinLifetime": 3600000,
+	"onlineAccountSignaturesMaxLifetime": 86400000,
+	"rewardsByHeight": [
+		{ "height": 1, "reward": 100 },
+		{ "height": 11, "reward": 10 },
+		{ "height": 21, "reward": 1 }
+	],
+	"sharesByLevel": [
+		{ "levels": [ 1, 2 ], "share": 0.05 },
+		{ "levels": [ 3, 4 ], "share": 0.10 },
+		{ "levels": [ 5, 6 ], "share": 0.15 },
+		{ "levels": [ 7, 8 ], "share": 0.20 },
+		{ "levels": [ 9, 10 ], "share": 0.25 }
+	],
+	"qoraHoldersShare": 0.20,
+	"qoraPerQortReward": 250,
+	"blocksNeededByLevel": [ 10, 20, 30, 40, 50, 60, 70, 80, 90, 100 ],
+	"blockTimingsByHeight": [
+		{ "height": 1, "target": 60000, "deviation": 30000, "power": 0.2 }
+	],
+	"ciyamAtSettings": {
+		"feePerStep": "0.0001",
+		"maxStepsPerRound": 500,
+		"stepsPerFunctionCall": 10,
+		"minutesPerBlock": 1
+	},
+	"featureTriggers": {
+		"messageHeight": 0,
+		"atHeight": 0,
+		"assetsTimestamp": 0,
+		"votingTimestamp": 0,
+		"arbitraryTimestamp": 0,
+		"powfixTimestamp": 0,
+		"qortalTimestamp": 0,
+		"newAssetPricingTimestamp": 0,
+		"groupApprovalTimestamp": 0,
+		"atFindNextTransactionFix": 0,
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 6,
+		"calcChainWeightTimestamp": 0
+	},
+	"genesisInfo": {
+		"version": 4,
+		"timestamp": 0,
+		"transactions": [
+			{ "type": "ISSUE_ASSET", "assetName": "QORT", "description": "QORT native coin", "data": "", "quantity": 0, "isDivisible": true, "fee": 0 },
+			{ "type": "ISSUE_ASSET", "assetName": "Legacy-QORA", "description": "Representative legacy QORA", "quantity": 0, "isDivisible": true, "data": "{}", "isUnspendable": true },
+			{ "type": "ISSUE_ASSET", "assetName": "QORT-from-QORA", "description": "QORT gained from holding legacy QORA", "quantity": 0, "isDivisible": true, "data": "{}", "isUnspendable": true },
+
+			{ "type": "GENESIS", "recipient": "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v", "amount": "1000000000" },
+			{ "type": "GENESIS", "recipient": "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK", "amount": "1000000" },
+			{ "type": "GENESIS", "recipient": "QaUpHNhT3Ygx6avRiKobuLdusppR5biXjL", "amount": "1000000" },
+			{ "type": "GENESIS", "recipient": "Qci5m9k4rcwe4ruKrZZQKka4FzUUMut3er", "amount": "1000000" },
+
+			{ "type": "ACCOUNT_FLAGS", "target": "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v", "andMask": -1, "orMask": 1, "xorMask": 0 },
+			{ "type": "REWARD_SHARE", "minterPublicKey": "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP", "recipient": "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v", "rewardSharePublicKey": "7PpfnvLSG7y4HPh8hE7KoqAjLCkv7Ui6xw4mKAkbZtox", "sharePercent": 100 },
+
+			{ "type": "ACCOUNT_LEVEL", "target": "QgV4s3xnzLhVBEJxcYui4u4q11yhUHsd9v", "level": 1 },
+			{ "type": "ACCOUNT_LEVEL", "target": "QixPbJUwsaHsVEofJdozU9zgVqkK6aYhrK", "level": 1 },
+			{ "type": "ACCOUNT_LEVEL", "target": "QaUpHNhT3Ygx6avRiKobuLdusppR5biXjL", "level": 1 },
+			{ "type": "ACCOUNT_LEVEL", "target": "Qci5m9k4rcwe4ruKrZZQKka4FzUUMut3er", "level": 2 }
+		]
+	}
+}

src/test/resources/test-chain-v2-reward-scaling.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-chain-v2.json

@@ -46,7 +46,9 @@
 		"newAssetPricingTimestamp": 0,
 		"groupApprovalTimestamp": 0,
 		"atFindNextTransactionFix": 0,
-		"newBlockSigHeight": 999999
+		"newBlockSigHeight": 999999,
+		"shareBinFix": 999999,
+		"calcChainWeightTimestamp": 0
 	},
 	"genesisInfo": {
 		"version": 4,

src/test/resources/test-settings-v2-reward-levels.json

@@ -0,0 +1,7 @@
+{
+  "restrictedApi": false,
+  "blockchainConfig": "src/test/resources/test-chain-v2-reward-levels.json",
+  "wipeUnconfirmedOnStart": false,
+  "testNtpOffset": 0,
+  "minPeers": 0
+}