I feel I can now safely say I had zero hive loss this winter. Compared to 75%, 50%, and 25% respectively for previous years.
I think the reason is because of what I read another keeper is doing even further North and wetter locale than I. But the point of the whole matter is leave the bottom of the hive open.
I can hear the screams now. Yep, year before last I left one hive open....It went into that winter the weakest hive and came out the strongest of the bunch. This year I left all 4 hive bottoms open. Sure it has been a mild winter, but also very humid/wet, so it is a wash in my book
So, what I do is use a screened base. Next up is a Miller board. It is important that the slats are 90 degrees to the frame so that air flow is jumbled and not direct. Then my normal boxes. A Vivaldi board on top with obviously the cover ( have a mix of garden tops and flat tops.)
Anyhow, I am feeding since winter has been so warm. We have trees blooming already, pollen all over the place, not too many flowers or sources of nectar. I still have not broken the seals on the boxes and looked around inside, just opened the top to put a feeder in.
I still expect a hard freeze too. I am not giving lots of feed, they are on something, but I expect the cold or rain to shut them down again between now and the real spring.