got home this aftnoon to find these two "locked together"
the large one was trying to use its leg to flick the other one off
the small one at the bottom is upside down
eventually the big "bumbler" tried to fly off, but they both tumbled onto the path - the large one was 1st to pull itself round & buzz off - the smaller one took a while, but eventually went off strongly
cant remember seeing Bees behaving like that previously . . .