Re: Indoor wintering
For what it is worth, in post 9, there is a CAPA link to a Beaverlodge research paper. Realize your hives will not be raising much brood, but would seem ideal hive relative humidty is 40%.
"This water is important to the bees and they use it to dilute honey, feed brood and flush metabolic wastes from their bodies. Nonetheless, some of this water escapes as a vapour, which in itself is important as brood develops best at 40% relative humidity."
Zone 3b. If you always do what you always did, you'll always get what you always got!