I've been following this development also. This parasitic fly is known to go after bumblebees and paper wasps, and has only recently been noticed in tame honeybees.

We had a collapse in the population of our wild bumblebees last spring, and don't know why. They rebounded later in the year, but it's a worry. No bees, no food.

I wonder what the habitat range of this nasty little fly is?