HERE (<---) is an official B1G article discussing transfers within the conference. As I understand it, unless the intra-B1G transferring student gets a "Complete Release" from his original B1G school, he would both seat out a year AND lose a year of eligibility. You can think that the rule simply states that the sit-out year "counts" as a normal year for the purpose of eligibility.
Best I can tell, the eligibility loss applies equally to grad transfers. But since grad transfers typically only have one year of eligibility left, they couldn't possibly afford to lose it in order to transfer to another B1G institution. Hence, a B1G graduate wishing to transfer into another B1G school de facto NEEDS the Complete Release from his/current school.
The articles says nothing about the possibility of a "partial release", where the original school may exclude specific schools (for example, its in-state rival).
Best I can tell, the eligibility loss applies equally to grad transfers. But since grad transfers typically only have one year of eligibility left, they couldn't possibly afford to lose it in order to transfer to another B1G institution. Hence, a B1G graduate wishing to transfer into another B1G school de facto NEEDS the Complete Release from his/current school.
The articles says nothing about the possibility of a "partial release", where the original school may exclude specific schools (for example, its in-state rival).