I did a bee presentation with bees on Friday, the latest I have ever done. I had to put bees in the observation hive on Wednesday when it was warm, and did not get them back in their hive until this afternoon. I used a nuc with a late July swarm/abscond. The nuc was not massively strong, but ok. There was no capped brood, but was an area smaller than a tennis ball that had eggs, larvae and the queen. The scary part, aside from the weather, is the number of SHB in the nuc. The bees had made their own propolis trap on the top bar of 1 frame, but I wasn't prepared and didn't have a hive tool ready to crush the gathered beetles. I was less concerned about chilling brood than I was about trying to return bees to the nuc when it was too cool and too windy for the adult bees that came off frames to be able to fly back on their own.
I would never have attempted this with a functioning hive I want to over winter, but I am willing to experiment with a late season abscond.