(a) No obligation or liability bearing interest at a rate in excess of 6 percent per year incurred by a service member before that person’s current period of military service shall, except as provided in subdivision (b), bear interest at a rate in excess of 6 percent per year as follows:

1. (1) For an obligation or liability consisting of a mortgage, trust deed, or other security in the nature of a mortgage, or any student loan, during any part of the period of military service and one year thereafter.
2. (2) For any other obligation or liability, during any part of the period of military service and 120 days thereafter.