I don't go by the range yardages much. I'd say just go mostly by your old yardages and swing a little easier.
I'd also like to add that I too am 100% done with range mats also. I've said it before but did it last night. Today I hit about 30% of my shots extremely thin and
topped a friggen 8iron!! I literally have not topped a shot since about March 2005. Thin is bad enough, I never hit shots thin like that. It took me about 15 holes before my ballstriking came back and I stuck a 9iron to 6 feet with a nice big divot. Mats don't give up divots and I end up shallowing out my path to hit off them.