Notwithstanding Section 852.108, a person who retired because the department in the municipality in which the person worked was privatized and who later resumes employment in the same department or a successor department in the person's reemploying municipality again becomes a member of the retirement system and the person's retirement annuity is not suspended in the same manner provided by Section 852.109 for a person who resumes employment with a different municipality.
Tex. Gov't. Code § 852.1085