The colony in Hive B has failed or absconded. The hive is now completely empty.
The colony has always been small. In a year they built only 5 frames of comb (on National deep frames). I thought that maybe the effort of being at height had over-stressed them so I moved the colony from the out apiary to my back garden. I placed them under an apple tree in the hope that they would recover. There is good forage and they were at ground level.