Might I suggest getting a third matching tire?

It is not uncommon to get uneven mileage from tires - necessitating say two rears for one front. Unfortunately, by the time you wear out the first one, that model of tire with probably be discontinued. Thus it is useful to have a third matching tire waiting on the shelf.

You should also expect to eventually lose a tire to a road hazard. Having a matching third tire lets you get back on the road without having either mismatched tires, or having to buy two new tires.

Right now during the transition season, you could use your outdoor tire on the trainer. Next spring, after the spring transition season, you could install the third tire and keep the trainer worn one as a spare.