Tex. Ins. Code § 1551.104
(a) Subject to Sections 1551.101 and 1551.102, each full-time employee is covered automatically by the basic coverage plan for employees and each annuitant is covered by the basic coverage plan for annuitants unless:
Added by Acts 2001, 77th Leg., ch. 1419, Sec. 3, eff. June 1, 2003.
Amended by Acts 2003, 78th Leg., ch. 366, Sec. 2.06, eff. Sept. 1, 2003.
Acts 2005, 79th Leg., Ch. 899 (S.B. 1863), Sec. 4.01, eff. August 29, 2005.