A young queen for the winter

Every winter four or five colonies in a hundred come out alive with a queen problem nobody can fix in time. The reason is the calendar. A new queen has to mate with the district's drones, and from August the colonies throw their drones out. A queen that fails after that cannot be replaced until spring, and the colony dwindles.

The sign is in the frames: no eggs and no young larvae, and no virgin on her way. A colony in that state has three or four weeks. From May to September the answer is a mated queen from a breeder, laying within a week.

Older queens fail more often.