At least if Taysom's decision is about where he plays and not if. If he plans to play Id think he would need to preparing for that offense by spring. At least learning it. Even at Virginia there will be adjustments any every other option including BYU will be different from what he's ran. Even if he can't practice I can't see a positive of not being around his team during spring ball.
If it's down to BYU or not playing, seems the same applies. He'd want to learn the system and Taysom strikes me as a man who would want the team to know what they have so they can also prepare. Moot point as far as I'm concerned