code: func (f *Field) RemoveAvailableShard(v uint64) error {
  	f.mu.Lock()
  	defer f.mu.Unlock()
  
  	b := f.remoteAvailableShards.Clone()
  	if _, err := b.Remove(v); err != nil {
  		return err
  	}
  	f.remoteAvailableShards = b
  
  	return f.unprotectedSaveAvailableShards()
  }
docs: // RemoveAvailableShard removes a shard from the bitmap cache.
  //
  // NOTE: This can be overridden on the next sync so all nodes should be updated.