Tex. Fam. Code § 3.307
(b) On the motion of either spouse, the court shall amend or vacate the original order after notice and hearing if:
Added by Acts 1997, 75th Leg., ch. 7, Sec. 1, eff. April 17, 1997.
Amended by Acts 2001, 77th Leg., ch. 217, Sec. 24, eff. Sept. 1, 2001.