Yep. Even some of the old Bluet stoves worked way up high, and they were 100% butane which turns to liquid at 31F/-0.5C. If you're going to be above 26,000' (8000m), feel free to use your canister stove.

Wish I could give you a formula as to how cold you can go at a given altitude. I saw a chart showing the relationship between temperature and altitude for gas canisters once in an old copy of "Off Belay" magazine. Maybe I can find a copy and post that.

HJ