No, apparently they’re just hot. But if they keep being too hot then they might bugger off, so I guess thumbs up for the heatwave?

Oy, mate! do you have a loicense for those bees then?

We had bees in our eves a couple of years ago. The advice: unless they're causing problems (stinging people, or causing structual damage) then leave them be. They'll all leave at the end of the season, and unlikely to return. Worked for us (thankfully they weren't causing us a major problem).