Both really. Sports cars have summer, but also winter tires too (perf snow/all season on other): when the temps get into the 40's the summers come off as they are not really well suited for cold days. This is typically not hard to do with the advent of Doppler radar: you see it getting colder. The freakish snow in October means they stay inside
For the sedans, I push it a bit later to December with HP A/S tires and snows. Yes I swap lots of tires, but to me its worth it for the few months of snow/slush and better grip and safety.
- b