You don't "Burn" your redshirt year if you play unless you're a 4th year player, haven't redshirted, and play more then 4 games. Any of the freshman now who don't redshirt this season can redshirt in any of the subsequent seasons. They're just are not taking their redshirt this season.
If they're good enough to have a significant role as a true freshman, then they're likely not going to stay for a 5th season unless they get hurt and use their redshirt during the season they get hurt.
If they're good enough to have a significant role as a true freshman, then they're likely not going to stay for a 5th season unless they get hurt and use their redshirt during the season they get hurt.