Swarming or supercedure?

[Sutty]

I have a colony which is the result of a walk-away split on 23rd may, of a brood nest consisting of 2 shallow national boxes. This was the queenless half. I wouldn't normally do this but wanted to get them off the very old shallow frames, and increase. I checked it two weeks ago and saw no brood (though I must have missed eggs and young larvae),then 1 week ago brood was present both sealed and unsealed. The bees are really bad for running around on the comb which makes inspecting difficult.
Today I again couldn't see a queen, looked hard for eggs (hand lens/torch), could only find several day-old larvae, sealed brood, and about 10 queen cells. Some of these were nice long cells at the bottom of frames, some looked like emergency cells in an arch in the comb face (I should have taken photos).
So I think either I have missed a swarm (though there isn't noticeably less bees present) or they are superceding.
I've cut the cells back to one open one, and put 2 cells in an incubator at 37C. (As luck would have it I breed chickens too). Gives me a bit of insurance and I could make up mating nucs.
Questions:
1. What do you think is happening? Swarm, supercedure, something else?
2. Anything I should have done differently? (Apart from not starting with a walk-away split)
3. What temperature and humidity should I incubate at?

 

[Erichalfbee]

1. Did you damage/kill the queen at last inspection? Certainly not supersedure
3. 35C 50%

 

[Sutty]

1. Did you damage/kill the queen at last inspection? Certainly not supersedure
3. 35C 50%

I wondered that, but some looked like they were started from cups

 

[Erichalfbee]

Some strange stuff going on with bees this year....lot of it seems completely daft if you are a bee.
If the bees are runny ....cut your losses and take this opportunity to re-queen. I wouldn't be making more queens with these genes

 

[Sutty]

Some strange stuff going on with bees this year....lot of it seems completely daft if you are a bee.
If the bees are runny ....cut your losses and take this opportunity to re-queen. I wouldn't be making more queens with these genes

I'll probably dequeen and unite it with a nicer colony at the end of the season.

 

[Sutty]

Well I looked again today. This morning one of the QCs I put in the incubator had emerged and looked ok. I've run her into the brood chamber after cutting out all new QCs, the one I had left has gone into the incubator. We'll see what happens.
This hive is probably going to be united with a better colony later