There seems to be a lot of late supersedure where the chance of a virgin getting mated is minimal.
I thought at first this might have been a supersedure but all I found a week later was a few emergency queen cells.
One problem I have noticed requeening by removing the floor of an Apidea is that the queen is sometimes still in the Apidea a week after uniting.
When this happens I lift out the Apidea frame with the queen and let her walk on to one of the frames in the brood box.