1 CFR § 18.17 - Effective dates and time periods.
(a) Each document submitted for publication in the Federal Register that includes an effective date or time period should either set forth a date certain or a time period measured by a certain number of days after publication in the Federal Register. When a document sets forth a time period measured by a certain number of days after publication, Office of the Federal Register staff will compute the date to be inserted in the document as set forth in paragraph (b) of this section.
(b) Dates certain will be computed by counting the day after the publication day as one, and by counting each succeeding day, including Saturdays, Sundays, and holidays. However, where the final count would fall on a Saturday, Sunday, or holiday, the date certain will be the next succeeding Federal business day.
(c) In the event an effective date is dependent upon Congressional action, or an act of Congress or a dispositive Federal court decision establishes or changes the effective date of an agency's regulation, the issuing agency shall promptly publish a document in the Federal Register announcing the effective date.