Hi Peter,
I’ve had good success overwintering some hives in single 8-frame deeps. I still monitor them closely through the winter and add feed when needed. Typically, I use double deeps for overwintering, but last year I had a few colonies that hadn’t filled their second box, so I left them in singles rather than combining. After how well that went, I’m planning to overwinter more hives in singles this time around.
I’m also curious about running singles during the honey flow, though I haven’t tested that out yet, maybe next season.
I really enjoy the content Paul Kelly and the University of Guelph put out, their videos and plans are excellent. I’ve probably watched all of them a few times over. I even picked up some canvas to use as inner covers like Paul does, similar to the feed bags some folks here in Vermont use. I have extra if you’d like to try a few.
Another thing I would like to pick up are the polypropylene winter hive wraps(
https://www.ontariobee.com/sales-and-services/polypropolene-winter-hive-wrap-program) that University of Guelph as well as many other Canadian beekeepers use. However, I have not been able to source a place in the US and I'm not sure I'm dedicated enough to drive 4 hours each way for a pickup.