private void startNewHeightManager(final BlockHeader parentHeader) {
    createNewHeightManager(parentHeader);
    final long newChainHeight = getCurrentHeightManager().getChainHeight();
    futureMessageBuffer.retrieveMessagesForHeight(newChainHeight).forEach(this::handleMessage);
  }
Stop the current height manager by creating a no-op block height manager.

@param parentHeader the parent header
consensus/common/src/main/java/org/hyperledger/besu/consensus/common/bft/statemachine/BaseBftController.java