Managed to get about three hours of sleep, before getting up to check woodstove and the plumbing.
I got to the hot water in the bathroom just in time. Some spluttering, but eventually the water started to flow.
Checked outside temperature: we have achieved -1F. Indoors is around 50F (except, apparently, where the bathroom plumbing is located).
So, looks like I’ll just stay up until the sun and outdoor temperature rise (supposed high today will be a balmy 17F).
Fun times!