(a) The board of trustees of an independent school district that adopts a redistricting plan under Section 11.052 may provide for the trustees in office when the plan is adopted or the school district is redistricted to serve for the remainder of their terms in accordance with this section.
(b) The trustee district and any at-large positions provided by the district's plan shall be filled as the staggered terms of trustees then in office expire. Not later than the 90th day before the date of the first election from trustee districts and after each redistricting, the board shall determine the order in which the positions will be filled.