I checked the trap today and everything looks good. I watched the cone for an hour and a half, from 1:00 PM until 2:30 PM. There was a steady exodus of 5 to 10 bees per minute, and some had taken up residence in the hive enough to be leaving it and going straight to the fields. Others returning were going immediately into the hive with pollen on both hind legs. So far, so good. They had NOT found any new entrances, so I don't think they will after this time.
I didn't open the hive, so I don't know if I lost the brood last night. We had a heavy frost, but hopefully there were enough bees to cover it. I will check for queen cells next weekend, and if I don't have them, I will install another frame with eggs.