public Set<InternalDistributedMember> adviseRequiresTwoMessages() {
    return adviseNotInitialized();
  }
returns the set of all the members in the system which require both DistributedCacheOperation
messages and notification-only partition messages

@return a set of recipients requiring both cache-op and notification messages
@since GemFire 5.7
geode-core/src/main/java/org/apache/geode/internal/cache/BucketAdvisor.java