(a) A public employee must initiate action under the grievance or appeal procedures of the employing state or local governmental entity relating to suspension or termination of employment or adverse personnel action before suing under this chapter.
(b) The employee must invoke the applicable grievance or appeal procedures not later than the 90th day after the date on which the alleged violation of this chapter:
(1) occurred; or
(2) was discovered by the employee through reasonable diligence.
(c) Time used by the employee in acting under the grievance or appeal procedures is excluded, except as provided by Subsection (d), from the period established by Section 554.005.
(d) If a final decision is not rendered before the 61st day after the date procedures are initiated under Subsection (a), the employee may elect to:
(1) exhaust the applicable procedures under Subsection (a), in which event the employee must sue not later than the 30th day after the date those procedures are exhausted to obtain relief under this chapter; or
(2) terminate procedures under Subsection (a), in which event the employee must sue within the time remaining under Section 554.005 to obtain relief under this chapter.