The time for reply by an applicant to a request by the Office for certain action, shall be extended by the Commissioner only for good and sufficient cause, and for a specified reasonable time. A request for extension and appropriate fee shall be filed on or before the specified time for reply. In no case shall the mere filing of a request for extension require the granting of an extension or state the time for reply. [58 FR 42435, Aug. 9, 1993, as amended at 61 FR 248, Jan. 4, 1996]