There’s plenty of ways to split a hive:
Last Wednesday while taking honey frames to extract I noticed one hive with the lid half full of bees doing nothing. I had no honey to remove from that hive. I didn’t have time to check on the brood then on account of a lot of recent rain made the bees hungry. Therefore I couldn’t leave the honey frames sitting around very long.
It’s been raining on & off since then, it’s Saturday afternoon now. With a break in the weather, I went to return stickies. With the lid full of bees in mind, I took a brood box with me. I also remembered that I had to check on 2 splits to see if they are queen right.
After returning the stickies, I had 3 left. I quickly removed the lid to find it still half full of bees. I placed it on the ground upside down. Then I quickly checked the first split to discover it to be queen right. I shook the bees off the first brood frame I found before placing it over the bees in the lid. Did the same with the second split. Then I removed 3 honey frames covered in bees from the hive the lid came from, placed them in the brood box. Then one by one I placed the brood frames covered in bees into the brood box before finding 5 other frames to fill the gap before closing it up in readiness to bring home.
The last thing I had to do was replace the 3 honey frames with the 3 remaining stickies. Then come home.
I have no idea if the colony was preparing to swarm or not. With more rain threatening, I didn’t feel like getting into the brood of a strong colony. If they were thinking about swarming, the removal of all those bees should go a long way towards making them change their mind. My theory being that the bees in the lid would make up a lot of the numbers in the swarm.