(a) Except as provided in paragraph (d) of this section, the Board or General Counsel, or their designated representatives, as appropriate, may extend any time limit provided in this subchapter for good cause shown, and shall notify the parties of any such extension. Requests for extensions of time shall be filed in writing no later than five (5) days before the established time limit for filing, shall state the position of the other parties on the request for extension, and shall be served on the other parties.

(b) Except as provided in paragraph (d) of this section, the Board or General Counsel, or their designated representatives, as appropriate, may waive any expired time limit in this subchapter in extraordinary circumstances. Request for a waiver of time limits shall state the position of the other parties and shall be served on the other parties.

(c) The time limits established in this subchapter may not be extended or waived in any manner other than that described in this subchapter.

(d) The time limits prescribed by 22 U.S.C. 4114(c) may not be waived.