Hi Thanks for the comments. Queen is not clipped. Weather's changed again so I don't want to open the hive. No queen cells last time I checked and the cluster have now returned to the hive. They still have enough room. Entrance is fully open but they were very busy. A point to remember is that quite a few of the bees were carrying pollen - that's why I didn't think it was swarming. Not enough bees for a swarm anyway. -- Joe