14 C.F.R. § 385.32
Unless, within the time provided by or pursuant to this part, a petition for review is filed or the Department gives notice that it will review on its own motion, staff action shall, without further proceedings, be effective and become the action of the Department upon the expiration of such period. A timely petition for review filed in accordance with the provisions of this section, or notice given by the Department of review on its own motion, shall stay the staff action pending disposition by the Department, unless the Department determines otherwise or unless the staff action provides otherwise in accordance with subpart A of this part. However, in cases where the Department's regulations provide that permissions or approvals are granted, or that other legal effects result, within a stated period from the filing with the Department of a prescribed document, unless the Department gives notice to the contrary or takes other action within said period, such notice given or action taken by a staff member under delegated authority shall toll the running of such period. A timely petition for review of staff action which is not stayed by its filing which is received after or not acted upon before the effective date of the action shall be entertained and disposed of on its merits as a petition for reconsideration.
14 C.F.R. §385.32