Tex. Transp. Code § 1006.053
(b) If there is a vacancy during a term, the governor shall appoint a replacement who meets the requirements of the vacant office to fill the unexpired term.
Transferred, redesignated and amended from Vernon's Civil Statutes, Section 3(e), Art/Sec 4413(37) by Acts 2019, 86th Leg., R.S., Ch. 594 (S.B. 604), Sec. 5.07, eff. September 1, 2019.