The bees are clustering. Check that hive entrances are clear and that the bees have enough food. Consider treating with oxalic acid
After a disappointing season weather-wise the bees have started to cluster but will take occasional cleansing flights in brief sunny spells.
Bees die on the wing in the active season. During winter, the old bees will die inside the hive and the workers will drag the corpses towards the entrance. Sometimes a build-up can block their exit, especially if a mouse guard is fitted. Make sure that this has not happened, and scrape away any dead bees that are causing a blockage.
Autumn was mild until mid-November so bees were making flights and using up stores later than “normal”. Heft your hives to feel the weight; they should not be light but bear in mind that the recent weather will have made wood damp, which could give a false positive. Gently lift at one side until the hive only just begins to rise; then do the same at the other (bees may have used stores at one side of the hive but not the other). To be safe, you can give the bees a block of fondant. They will ignore it if they don’t need it, but you can monitor their preference by checking how much they have taken after a few weeks.
Queens tend to continue laying until late in the year, here in the south of UK; and sometimes they don’t take a break. Nevertheless, Varroa don’t take a break either so you should consider whether you wish to administer oxalic acid, either dribbled or sublimated, to minimise the Varroa load. Many experts advise it, so that spring build-up is not hampered by a heavy infestation.