Well, the hive that swarmed has produced a virgin queen. I got lucky and was in the yard when she returned to the hive from a mating flight! Yay! Was excited to see her. she landed on the face of the hive and was immediately surrounded by a few bees. They escorted Her Majesty indoors away from my prying eyes. Now on to the hive with the queen cups. Yes, they were preparing to swarm on me! I went back to check again and the cups were no longer empty! I split the hive. I did two splits. I moved one split and the one with the original queen to the other side of the yard. Now, hopefully in a few weeks I will have doubled my hives and have prevented a swarm! Fingers crossed!