increases applicable to outstanding balance Except as provided in clause (iii), a postsecondary educational lender or servicer may not increase the interest rate or other fee applicable to an outstanding balance on a postsecondary education loan. (iii) Exceptions The requirements under clauses (i) and (ii) shall not apply to— (I) an increase based on an applicable variable interest rate incorporated in the terms of a postsecondary education loan that provides for changes in the interest rate according to operation of an index that is not under the control of the postsecondary educational lender or servicer and is published for viewing by the general public