(a) A charter granted under Section 12.052 or 12.053 may be revised:
(1) with the approval of the board of trustees that granted the charter; and
(2) on a petition signed by a majority of the parents and a majority of the classroom teachers at the campus or in the program, as applicable.
(b) A charter granted under Section 12.0521 may be revised with the approval of the board of trustees that granted the charter. A charter may be revised under this subsection only before the first day of instruction of a school year or after the final day of instruction of a school year.