I have been trying to deal with an infestation of flies
since last fall and I can’t seem to get rid of the buggers.

These are not fruit flies or fungas gnats. I have had both
and have dealt with them both. These flies are small like both of those, with a
body similar to a fruit fly but darker. Decent fliers.

I keep the food buried, eggs are still laid and maggots and
flies start to appear. I started with two bins but through excessive harvesting
multiple times to clean the bin (trying to get rid of maggots and flies) the
worm population has dwindled. During these cleanups I harvest, clean the bin
and then move the bin away from the infested area of the house (I actually live
in a house that has been converted to apartments, but have stashed the cleaned
up bin in the basement for example). Each time I think I have it the flies
gradually start to appear again.

The flies don’t seem to bother the worms at all, I just don’t
want them in my apartment. I also can’t keep the bins in the basement long
term. It’s starting to warm up here in Ontario, but it’s still not that warm
and there’s still a lot of snow on the ground. How early can I transfer the bin
outside without killing the worms? Will the flies “move on” if I move
everything outside, at least when it starts warming up a bit more? Would I have
to wait until fall to move things back inside if I don’t want to bring a breeding
pile of bugs in with me?

Don’t know if the worm population can survive another full
harvest and cleaning, just trying to figure out other options here.

Thanks!