Queen is only the queen if the workers agree. Workers do not let queens destroy swarm queens or superceder queens.
Days. They are staggered for afterswarms.
"This laying commonly continues thirty days. The bees on the twentieth or twenty-first lay the foundation of several royal cells. Sometimes they build fifteen or twenty; we have even had twenty-seven. When the cells are three or four lines high, the queen lays those eggs from which her own species will come, but not the whole in one day. That the hive may throw several swarms, it is essential that the young females conducting them be not all produced at the same time. One may affirm, that the queen anticipates the fact, for she takes care to allow at least the interval of a day between every egg deposited in the cells. It is proved by the bees knowing to close the cells the moment the worms are ready to metamorphose to nymphs. How, as they close all the royal cells at different periods, it is evident the included worms are not all of an equal age."--François Huber, New Observations on the Natural History Of Bees Volume I
There is much more detail in the book referenced above (and the first volume of the 1809 version is free on my website).
But the short version is this. The old queen leaves with the primary swarm shortly after the first queen cell is capped (could be one day or more depending on the weather). About seven days later that first cell emerges. If they want to swarm again, they protect the other cells from that queen and confine those queens if they try to emerge, until she leaves and then they let out a another queen. This continues until they do not want to afterswarm anymore and they let that queen kill the rest."
I recently took over the care of a hive which swarmed 16 days ago. A couple days post swarm I stole a frame of honey and a second frame with a queen cell as insurance for the swarm as I was unsure if we had captured the queen. I only saw 3-4 frames as it was not my hive.
I am about to move the hive and was attempting to remove some honey frames to lighten the load, and discovered another capped queen cell and they had consumed a boatload of honey. They also had not built any comb on the two empty frames I used to replace the honey frames.
Again I did not inspect the entire hive, as they had the most enormous orientation flight going on, or at least I thought.
Did they consume the honey to make space for eggs? Why no new comb? The farm they live on was recently cut as the farmer relocated. We're they just hungry because their habitual forage is gone?
Mostly are they going to swarm again and is there anything I can do. Would requeening change their minds?