42 CFR § 422.1018 - Notice and effect of initial determinations.
(a) Notice of initial determination. CMS, as required under 422.756(f)(2), mails notice of an initial determination to the affected party, setting forth the basis or reasons for the determination, the effect of the determination, and the party's right to a hearing, and information about where to file the request for hearing.
(b) Effect of initial determination. An initial determination is binding unless -
(2) CMS revises its decision.