821.52—General.

(a) Applicability. This subpart shall apply to any order issued by the Administrator under 49 U.S.C. 44709 as an emergency order, as an order not designated as an emergency order but later amended to be an emergency order, and any order designated as immediately effective or effective immediately.
(d) Waiver. Except as provided in § 821.54(f), or where the law judge or the Board determines that it would unduly burden another party or the Board, a certificate holder (respondent) affected by an emergency or other immediately effective order of the Administrator may, at any time after filing an appeal from such an order, waive the applicability of the accelerated time limits of this subpart; however, such a waiver shall not serve to lengthen any period of time for doing an act prescribed by this subpart which expired before the date on which the waiver was made.