Actually there is a limit. You can have 85 scholarships max on a team. So if the team has 85 currently on it, then technically they can add 25 early enrollees to the spring roster that will count towards the next years class if there is 25 spots on the 85 roster that will be leaving.
Backcounting only counts regarding the 25 per year number allowed to sign in a class, a team can only have 85 total for the year.