Yes you can in theory turn around; however, ensure your checked in for the return (I assume with no bags) before you depart YYZ so you have no issues getting offloaded if your inbound is late but they don't push back the checkin for the outbound and ensure your legitimately able to enter the country if something does get wrong such as you getting held up. That is one heck of a mileage run. Wouldn't it make more sense to move to January and just get instant recognition when you hit 100k the next year?