private String logBlockNumberMaybeHash(
      final long blockNumber, final Optional<Hash> maybeBlockHash) {
    return blockNumber + maybeBlockHash.map(h -> " (" + h + ")").orElse("");
  }
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