Erm? Not this one but another nuc had a "sealed" QC. A choice to leave it or let the young queen come out and potentially kill the old queen which was laying with brood at all levels.
The books say don't go in a hive unless you can comfortably walk around in shorts and a t shirt. But to a Yorkshireman (or woman) that could mean -20 deg C and a few feet of snow on the ground. So the books are wrong. But that doesn't mean poking around the hive trying to fix problems that might not exist and over which you have little control is a good idea!
If a new queen emerges in a queenright colony it either swarms or it doesn't swarm. This time of year, this far up north, with the weather we have been having, the bees won't swarm. The latest swarm I've
ever had was end of August/Early September due to a (forced by circumstances) heavy feed and bees that preferred to backfill a broodbox than store in a super.
So you might end up with two queens in a hive. So what? You may get scrapping between virgins, but two queens, in a well populated hive, one mated no matter how badly and a recently emerged virgin
will be kept apart. If the new one by some miracle mates and is accepted then the old one may be killed, but the old one is just as likely to be around next spring, maybe side by side on the same frame with the new queen. (Many beekeepers see one queen and never even consider looking for another)
But as the weather locally got worse and the nights got a lot colder the queen cell might have been torn down, or recently emerged new queens might have been dumped out the hive (I've seen them dumped on the roofs of hives before when bees stuck with their original queen) Bees want to survive the winter and while they may sense a queen failing and try to raise another one, they won't normally kill the old one before the new one is properly established. But having said that they can still do strange things that the beekeeper can't understand and all the books ever written never mention.
Yes I've wrote a lot for someone who said words fail me, but fiddling in a hive this far north, in October, even in a very good year, is IMHO a bad idea, with the recent conditions it's just plain daft. Let them get on with it. They might make mistakes, but they have a few million more years experience of making mistakes and getting it right than even the oldest and most experienced beekeeper.