Son's first year at JuCo there was 55 or so during the fall season. When asked the coach said not to worry, he won't have to make cuts. They'll self cut by spring. Sure enough, a few became ineligible due to grades, some injured (redshirt) and the rest self cut (quit). Come spring the roster was at 35.
Additionally by the last month the active roster was down to 28 or so as more quit due to lack of playing time, grades and I think maybe one or two injuries.