Was not avoiding your question, but neglected to do it at the time.
The colony has to regulate population through the whole season to be proportional to stores and cavity size. It's absolutely necessary to colony survival. Their math department does a good job of projecting the brood volume required to stay in proportion. That means they have to account for the 3 weeks of a brood cycle, incoming forage available, brood needing feeding, and stores on hand. They need to be somewhat clairvoyant to estmate the staus 3 weeks ahead of time.

Generally, it's a continuous, smooth change in brood volume throughout the whole season. Occasionally, a major out-of-balance condition prompts a faster change. (We had lots of reports last season in drought areas of brood shut-down.) That's an emergency level change in brood volume.

It would be interesting for others if you could figure out exactly what prompted your emergency action.