(a) An obligor and obligee may agree on a reduction in or termination of income withholding for child support on the occurrence of one of the following contingencies stated in the order:
(1) the child becomes 18 years of age or is graduated from high school, whichever is later;
(2) the child’s disabilities of minority are removed by marriage, court order, or other operation of law; or
(3) the child dies.
(b) The obligor and obligee may file a notarized or acknowledged request with the clerk of the court under § 158.011 for a revised judicial writ of withholding, including the termination of withholding.

(c) The clerk shall issue and deliver to an employer of the obligor a judicial writ of withholding that reflects the agreed revision or termination of withholding.
(d) An agreement by the parties under this section does not modify the terms of a support order.