That's an easy thing to test ... a few hundred RFID-chipped workers and an array of hives with readers/detectors across their entrances. It would only cost a couple of hundred thousand quid. Alternatively, a couple of POSCA pens and some willing project students willing to watch hive entrances for a few days. That would only cost £10.40

I think the recent data from Seeley indicates that something like 20-30% of drones are found in hives other than the one they were raised in ...