the effective date of the change or increase. (B) Material changes in terms The Bureau shall, by regulation, establish guidelines for determining which changes in terms are material under subparagraph (A). (2) Limits on interest rate and fee increases applicable to outstanding balance Except as provided in paragraph (3), a covered lender, servicer, or assignee may not increase the interest rate or other fee applicable to an outstanding balance on a postsecondary education loan. (3) Exceptions The requirements under paragraphs (1) and (2) shall not apply to— (A) 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 covered lender, servicer, or assignee and is published for viewing by the general public