(a) Request to foreclosure commissioner
If the Secretary, as holder of a single family mortgage, determines that the prerequisites to foreclosure set forth in section 3755 of this title are satisfied, the Secretary may request the foreclosure commissioner to commence foreclosure of a single family mortgage. Upon such request, the foreclosure commissioner shall commence foreclosure of the mortgage, by commencing service of a notice of default and foreclosure sale in accordance with sections 3757 and 3758 of this title.

(b) Designation of substitute foreclosure commissioner
After commencement of a foreclosure under this chapter, the Secretary may designate a substitute foreclosure commissioner at any time before the time of the foreclosure sale, and the foreclosure shall continue without prejudice, unless the substitute commissioner, in that commissioner's sole discretion, finds that continuation of the foreclosure sale will unfairly affect the interests of the mortgagor. If the substitute commissioner makes such a finding, the substitute commissioner shall cancel the foreclosure sale, or adjourn such sale in accordance with section 3760(c) of this title.

(c) Written notice
Upon designation of a substitute foreclosure commissioner, a copy of the written notice of such designation described in section 3754 of this title shall be served—

(1) by mail, as provided in section 3758 of this title (except that the minimum time periods between mailing and the date of foreclosure sale prescribed in such section shall not apply); or

(2) in any other manner which, in the substitute commissioner's sole discretion, is conducive to achieving timely notice of such substitution.