The bees would likely already have collected more than enough earlier in the season so they would not need to add anymore unless available (they don't 'decide' they just collect if forage is available), but if those stocks have been plundered by humans (the beekeeper), or the colony is a small or a late swarm sufficient stocks may never materialise - depends on the season and the winter.
She may be laying late into the autumn - depends on the origin of the queen, for instance. She may never stop laying, even if it is just a few eggs, if in a warmer climate. I daresay in the warmest countries (not the UK) they never really cluster at all, or for very long.
We, as beekeepers, try to make sure they are sufficiently provisioned for the winter and spring-time colony expansion. That, or we would soon become non-beekeepers!