Tex. Local Government Code § 6.011: AUTHORITY TO CHANGE TO TYPE A GENERAL-LAW MUNICIPALITY.

(a) A municipality incorporated in any manner other than as a Type A general-law municipality may change to a Type A general-law municipality if the municipality:

(1) has 600 or more inhabitants;

(2) contains one or more manufacturing establishments within its corporate limits; or

(3) is incorporated under any law of the Republic of Texas.

(b) A municipality that makes the change shall operate under the law applying to a Type A general-law municipality instead of operating under any charter or law that previously governed the municipality.

Acts 1987, 70th Leg., ch. 149, Sec. 1, eff. Sept. 1, 1987.