In Indiana winterize it before the middle of Oct. A lot easier to do in good weather then trying to get it done in freezing temps.
And don't UN-winterize it untill you are in Southern GA. on your way to FL.
If not winterized by then, plan on a lot of repair's to the water lines, maybe busted water heater tank, fresh water tank etc. by the 1st of the year.
And it will take much, much longer and $$$ to fix, then doing a winterize.
I have been in IN. the last couple weeks visiting my old home town. Last 2 nights lows in the 40's Brrrrr!. Monday heading for my winter spot in Florida.
Last time I seen snow was in IN. 1999. And I haven't missed it any.