Ours is on a programmable timer, and since we lost the instructions for it, it has been set to come on at the same times (2 hours in the morning., an hour at lunch, an hour at teatime and then 2 hours before bedtime) but it does not know anything about BST
it can be manually overridden at any time, and first sign of sunshine usually sees it getting knocked off (even if it is -5 outside)
