(a) If the federal government has referred a complaint to the commission or has deferred jurisdiction over the subject matter of the complaint to the commission, the commission shall promptly investigate the allegations set forth in the complaint.
(b) The commission shall investigate all complaints and, except as provided by Subsection (c), shall complete an investigation not later than the 100th day after the date the complaint is filed or, if it is unable to complete the investigation within the 100-day period, shall dispose of all administrative proceedings related to the investigation not later than the first anniversary after the date the complaint is filed.
(c) If the commission is unable to complete an investigation within the time periods prescribed by Subsection (b), the commission shall notify the complainant and the respondent in writing of the reasons for the delay.