1. (1) In computing any period of time, the date of the act or the event after which the designated period begins to run is not to be included. The last day of the period, as computed, is to be included unless it is a Saturday, Sunday, legal holiday, or a day when the Commission is closed. In this event, the period runs until the end of the next day, not a Saturday, Sunday, legal holiday, or day when the Commission is closed. When the time prescribed or allowed is one week or less, intermediate Saturdays, Sundays, and legal holidays shall be excluded from the computation. However, when the time is fixed by statute, the time shall be computed as provided in T.C.A. § 1-3-102.
2. (2) Any filing required by the Commission by a date-certain shall be filed with the Docket Manager by 2:00 p.m. on that date.

3. (3) When these rules, a notice, or any order entered in a proceeding requires or allows an act to be done in the proceeding or within a specified time, the Commission or Hearing Officer may, for cause shown, at any time:

   1. (a) Extend the specified time without motion or notice;
   2. (b) Order the period enlarged, if a motion is filed before the expiration of the period originally prescribed or as extended by a previous order; or
   3. (c) Upon motion after the expiration of the specified period, permit the act to be done where failure to act resulted from excusable neglect; but the time for taking any action may not be extended when that time is fixed by statute.

Authority: T.C.A. § 65-2-102. Administrative History: Original rule filed June 30, 2000; effective September 13, 2000. Editorial changes made by the Secretary of State pursuant to Public Chapter 826 of 2002 by replacing “Executive Secretary” with “Chair of the Authority”; effective March 28, 2003. Administrative changes made to this chapter on April 27, 2018 pursuant to Public Chapter 94 of 2017; “Tennessee Regulatory Authority” references were changed to “Tennessee Public Utility Commission,” “Authority” references were changed to “Commission,” “Authority Director” references were changed to “Commissioner,” and “Chief” references were changed to “Director.” Amendments filed August 11, 2025; effective November 9, 2025.