(a) A financing order must include a formulaic true-up charge adjustment mechanism that requires that the customer rate relief charges be reviewed and adjusted at least annually by the servicer or replacement servicer, including a subservicer or replacement subservicer, at time periods and frequencies provided in the financing order, to:
(1) correct any overcollections or undercollections of the preceding 12 months; and
(2) ensure the expected recovery of amounts sufficient to provide for the timely payment of customer rate relief bond principal and interest payments and other financing costs.
(b) True-up charge adjustments must become effective not later than the 30th day after the date the railroad commission receives a true-up charge adjustment letter from the servicer or replacement servicer notifying the railroad commission of the pending adjustment.

(c) Any administrative review of true-up charge adjustments must be limited to notifying the servicer of mathematical or clerical errors in the calculation. The servicer may correct the error and refile a true-up charge adjustment letter, with the adjustment becoming effective as soon as practicable but not later than the 30th day after the date the railroad commission receives the refiled letter.