@Override
  protected boolean operateOnPartitionedRegion(ClusterDistributionManager dm, PartitionedRegion pr,
      long startTime) throws CacheException {

    // This call has come to an uninitialized region.
    // This can occur as bucket grab Op is done outside the
    // d-lock.
    if (pr == null || !pr.isInitialized()) {
      return false;
    }

    if (logger.isTraceEnabled(LogMarker.DM_VERBOSE)) {
      logger.trace(LogMarker.DM_VERBOSE, "BucketBackupMessage operateOnRegion: {}",
          pr.getFullPath());
    }
    PartitionedRegionDataStore ds = pr.getDataStore();
    if (ds != null) {
      pr.getRedundancyProvider().finishIncompleteBucketCreation(bucketId);
    } else {
      logger.warn("BucketBackupMessage: data store not configured for this member");
    }
    pr.getPrStats().endPartitionMessagesProcessing(startTime);
    return false;
  }
This message may be sent to nodes before the PartitionedRegion is completely initialized due to
the RegionAdvisor(s) knowing about the existence of a partitioned region at a very early part
of the initialization
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/BucketBackupMessage.java