The department may not require the repayment of the principal of and interest on a loan made under AS 16.10.910 during the first six years of the loan. However, for a loan made under AS 16.10.910(a)(2), the department may defer repayment of the principal of and interest on the loan for an additional period not to exceed the first 11 years of the loan. The department may provide that interest on the principal of a loan made under AS 16.10.910(a)(1) does not accrue during a period not to exceed the first six years of the loan. For a loan made under AS 16.10.910(a)(2), the department shall provide that interest on the principal of the loan does not accrue during the first six years of the loan, and the department may provide that interest on the principal of the loan does not accrue during an additional period not to exceed the first 11 years of the loan.