Sorry to hear it. I lost a few to the SHB this season as well. Like you finally had to build new hives with traps and transfer colonies, that and changing to pvc pipe entrances w/ sticky tape seems to have turned the tide. I've got a video I'll get up @ some point of the bottom of a Perone (2'x2') with 3-4" of SHB larva piled in it squirming around. I was expecting the, "Hatch", from a recent cutout but it was worse than I've ever seen. Absolutely disgusting !
Cheers,
Drew