Any JUCO players who appear in more than two games or scrimmages in the Fall schedule - even if they never appear in another game that school year (maybe they left the school, or the coach is disciplining them for some reason) - will have that count as a season of eligibility used when they transfer to an NCAA Division I or II program.
Also, Division I revised a rule back in the summer that may help players moving forward, and possibly also retroactively, regarding Fall game appearances. The change is such that a player who appears in a scrimmage or exhibition game during the Fall, but is redshirted and doesn't appear any more that year (while a member of a Division I team) can take that season as a redshirt season.
This rule change would have helped one of my clients a few years ago had it been in effect at that time because he was charged with a season of competition only because he appeared in one Fall scrimmage game against a local minor league team that was just finishing their season.