I'm in my second year, attempting to over-winter 4 nucs and 2 hives this year. Here in Charlotte, NC, we have somewhat mild winters, with periods of dry breezy cold. I am using homemade slatted racks on two of my smallest nucs and my main two hives, with screened bottom boards on all 6 colonies. Should I close up any of my screened bottoms? Should I add in a top entrance to any or all of my hives, and is this necessary if I leave the screened bottom boards open? One of my nucs has small openings between the first and second boxes ... should I plug those up with hay or grass, add a top entrance ... both?

I don't think I've fed enough this fall, especially if this season will be as warm as last year, so I'm planning on sugar cakes at some point. My smallest nuc, population-wise, is a stack of three 5-frame deep boxes. If the top box frames aren't filled totally with capped honey/syrup, should I remove that entirely and it's empty single-frame feeder and feed once the bees have made it to the top of the second box? Is it a good practice to remove supers that are only partially full with some capped honey but mostly uncapped nectar for over-wintering and replacing with dry feed? (I was under the impression after my first year that the bees needed space to move vertically into over the course of winter ... maybe a mistaken impression?)

Thanks in advance, everybody!