sterling, i think i have enough because they don't break cluster much here. where you are, they probably don't stay clustered all winter.
my danger time is from the middle of February until we start getting something blooming which could be as late as the end of april, depending on weather..we will get some pollen from the filberts between mid Feb and the time the dandelions bloom. because we have such wet weather and getting into the hives in early spring is such a crap shoot, i put dry sugar on top of the inner cover over the winter. that way, if they break and need something, it is available. it also absorbs some of the moisture from the hive. i can replenish it with out worry of adding moisture to the hive or digging around in there. if they need it fine, if they don't, that's ok too.
as for getting them into that space, they pretty much put themselves there. in an established colony, i don't expand the brood box area during the year. if they find they need to use the honey super for a bit of brood, that's ok. i just wait them out and by late summer they have backfilled it with honey. my season is pretty short so they probably don't build up like a hive in Florida might.