20 CFR § 404.3 - General provisions.
(a) Effect of cross references. The cross references in the regulations in this part 404 to other portions of the regulations, when the word see is used, are made only for convenience and shall be given no legal effect.
(b) Periods of limitation ending on nonwork days. Pursuant to the provisions of section 216(j) of the act, effective September 13, 1960, where any provision of title II, or any provision of another law of the United States (other than the Internal Revenue Code of 1954) relating to or changing the effect of title II, or any regulation of the Commissioner issued under title II, provides for a period within which an act is required to be done which affects eligibility for or the amount of any benefit or payment under this title or is necessary to establish or protect any rights under this title, and such period ends on a Saturday, Sunday or Federal legal holiday or on any other day all or part of which is declared to be a nonwork day for Federal employees by statute or Executive Order, then such act shall be considered as done within such period if it is done on the first day thereafter which is not a Saturday, Sunday, or legal holiday or any other day all or part of which is declared to be a nonwork day for Federal employees either by statute or Executive Order. For purposes of this paragraph, the day on which a period ends shall include the final day of any extended period where such extension is authorized by law or by the Commissioner pursuant to law. Such extension of any period of limitation does not apply to periods during which benefits may be paid for months prior to the month an application for such benefits is filed pursuant to § 404.621, or to periods during which an application for benefits may be accepted as such pursuant to § 404.620.