I've always declined such opportunities: softie that I am, as a rule I retire my bikes for the winter before Christmas, and bring them into the spring sunshine around mid-March. I use the intervening 3 months or so for winter projects & winter sports--X-country skiing, hockey, skating. I've shied away from the extra expense of winter camping, but since my early days in Canada on a farm, I've have always been spooked by the problem of hypothermia.
There are some guys around Ottawa, fat-bike wallahs especially, who do winter riding, including camping. There are cabins and yurts that one can rent in nearby parks and skiers routinely do so. And, there are a few threads on crazyguy recounting bicycle travel in the Canadian and Siberian Arctic. I'm in awe of those cyclists -- well, awe mixed with a bit of morbid fascination.
Still ... late last Feb, the co-owner of my LBS said he was going up the Valley for a day of Fatbiking in the Snow, a festival as it were. (Winter Carnivals are standard practice hearabouts. Québec sets the standard, as you might guess: one of Gilles Vigneault's great anthems is "Mon Pays, C'est l'Hiver. Have a look & listen here,
https://www.youtube.com/watch?v=CH_R6D7mU7M, a hymn not just to winter but to human tolerance and solidarity.) Ooops -- back to the thread: I raised my eyebrows at the idea, as the daytime temps were around -20 to -25, without the windchill. Barely manageable if there's sunshine, as there often is at that temperature, though with the sunshine & high pressure, there's usually a northerly. Wisely, they called it off.
Those are extreme conditions, to be sure. If you can manage to keep dry(-ish), and there's not too much ice,
and there are warm-&-dry pubs nearby, go for it, sez I.
