I've been seeing wasps, flies, wild bees, and all kinds of creatures trying to get into the front entrance. I've been seeing the girls throwing out the intruders, too, literally grabbing them and taking them away or balling them up, heating them to kill them and then dumping all the bodies out the front door. There's a huge spider living under the hive, that gathers up all the bodies and eats them, leaving all only the wings. The spider's been a kind of amazing clean up crew.
I've smashed a few wasps just because they're so easy to spot and they move slowly in 50+ or even low 60 degree weather.
Tonight it's supposed to rain down freezing sleet, so I've finally reduced the entrance to the smallest setting, and took the feeder out, simply to give the girls less space they have to heat. I'm also putting the feeder in a place away from the hive so it'll lure the robbers there instead of to the hive, and the girls can still pick up sweets when they are energetic enough to be out flying. The last two brood boxes are heavy still with stores (or even the syrup, I imagine), and when I opened them to take out the feeder, there were still a lot of bees.
So I'm pretty hopeful about them lasting the winter. We'll see. I'll probably still put patties on around Christmas, in case they want them, but I've now zipped their boxes closed for the winter.