According to NCAA rule 126.96.36.199.2 the roster limit for bowl subdivision is 105. But this appears to only apply to participation in practice prior to the school's first day of classes or first contest, whichever occurs first. It appears that after either of those dates there is no limit on roster size (except for whatever limit the school itself chooses). This limit also does not appear to apply to spring practice or other off-season training which is controlled by separate rule (17.9.6). Unless it is hid somewhere else in the 430 page rule book. If someone has other information feel free to correct or clarify. But it appears that except for preseason camp until the first day of classes the team can have as many players on the roster as they desire.