So you've got your summer honey off, and you're treating with apistan.
Worried about fall swarming??  All those bees can't possibly be comfortable
in two deeps.  And with all that honey coming in, too -- but the queen
should keep laying.  What to do?  Many folks over the years have advocated
wintering commonly in *three* deeps  instead of two (e.g., C.L. Farrar),
claiming that all those pollen and honey reserves result in a much stronger
colony for the next season's early flows.  Brood rearing goes on full speed
ahead even in cool, wet spring weather, and you don't need to worry about
them slowing down.  These advantages have been borne out, but it also keeps
you from having to do any feeding (a real pain).  The bees in 3 deeps
during buildup don't get so congested and aren't as likely to swarm as
colonies in two boxes.  On the other hand, in early spring you can take
away the bottom brood chamber if you like, as it will be unoccupied, and
you're back to two.  Use the "spare" later for a swarm-control nuc, a/o
place it back on top later when you harvest your honey and insert the
apistan.  Then the bees have room to play in and store the fall crop.  Sure
it's an additional investment, but it would save you time and trouble worth
much more.  I winter a few colonies in 3's but would handle them all that
way if I had more equipment.  someday...