private boolean shouldImportBlockAtHeight(
      final long blockNumber, final long localHeight, final long bestChainHeight) {
    final long distanceFromLocalHead = blockNumber - localHeight;
    final long distanceFromBestPeer = blockNumber - bestChainHeight;
    final Range<Long> importRange = config.getBlockPropagationRange();
    return importRange.contains(distanceFromLocalHead)
        && importRange.contains(distanceFromBestPeer);
  }
Try to request the lowest ancestor for the given pending block or process the descendants if
the ancestor is already in the chain
ethereum/eth/src/main/java/org/hyperledger/besu/ethereum/eth/sync/BlockPropagationManager.java