With days becoming shorter, Queen's egg production reduces, reducing brood nest size. Worker bees start forcing almost all drones out of the hive. Inspect hives in 3-4 week intervals for health issues.
Only if required, provide bees with space to build and collect nectar (add a super). Start planning your hive close down for winter which involves compacting bees into one or two boxes to keep them warm.
Feed colonies with insufficient winter food stores with thick sugar syrup (2:1). Occasionally tiny swarms still occur but they have very little chance of surviving the winter.