Thanks in no small part to various threads on FT being copied to those at the top of BA, advice has now been given to all Flight and Cabin crew on what datum cabin temperatures are most comfortable for our passengers.

"We have received feedback that on some flights
customers are finding the cabin temperature too high,
especially on night sectors in premium cabins,
when sleeping with a blanket.
The recommended temperature for daylight
flights is 22-23°C and 21-22°C for night flights."

Hopefully this will start to bring cabin temperatures into a more comfortable range, but it is important that feedback is given to the crew on the day, as every flight is different, as are each passengers requirements.