34 Tex. Admin. Code § 43.8
Unless otherwise provided by statute, the time for filing pleadings or other documents may be extended, upon the filing of a motion, prior to the expiration of the applicable period of time, showing that there is good cause for such extension of time and that the need for the extension is not caused by the neglect, indifference, or lack of diligence of the party making the motion. A copy of any such motion shall be served upon all other parties of record to the proceeding contemporaneously with its filing. In the case of filings that initiate a proceeding or that are made before an appeal has been referred for an adjudicative hearing, the deputy director will determine whether good cause exists and whether an extension should be granted. In the case of filings made in a proceeding after TRS has referred the appeal for an adjudicative hearing, rules governing hearings before SOAH will control so long as the matter is before SOAH. If a matter is referred for an adjudicative hearing to a hearing official not affiliated with SOAH, then the rules of this chapter shall apply to the conduct of the hearing while pending before the hearing official. For matters returned by an administrative law judge or hearing examiner to TRS, either through dismissal from the adjudicative hearing docket or through issuance of a proposal for decision, the executive director may determine whether good cause exists and whether an extension should be granted. The executive director is authorized to rule on motions for extensions on matters directed to the Board if no Board meeting is scheduled before the expiration of the applicable period of time.
34 Tex. Admin. Code § 43.8