I have had a trapout set for almost a month. It was on the second floor balcony of a apartment. The tenant was great and she and her cat, Jackcat, watched the bees most of the time. She has had an severe life threatening allergic reaction to similar stings before and feared for her life from them but loved watching them.
I was planning to go over there last night around 7:30 PM and pick them up last night. They had stopped coming out of the bee escape. At 7:00 PM she called ma saying the entire patio had bees all over it, especially around the box and in the air. My wife and I grabbed bee vac equipment and headed right over. I had had the truck loaded with equipment but did not plan on needing a bee vac. Turns out the remainder of the bees up and moved out one hour before sunset and moved into the nuc box. 60 minutes after they started they were still slowly moving into the box. I suspect last night I had 2 queens in this box.
Tonight I will go into it and see what I have. I might use this hive to replace my observation hive that died this spring.
When I removed the board covering the hive entrance, there were no bees left in the old hive, even when I had a white light shining in it. In the future I will have to make sure that I keep the trap out on until no more bees come out for at least a day or so.
The last one that I did, I do not think that I waited long enough for the bees to swarm out.