public static int calculateRequiredFutureRCQuorum(final int validatorCount) {
    return (validatorCount - 1) / 3 + 1;
  }
Calculate required future RC messages count quorum for a round change.

@param validatorCount the validator count
@return Required number of future round change messages to reach quorum for a round change.
consensus/common/src/main/java/org/hyperledger/besu/consensus/common/bft/BftHelpers.java