As directed by a Federally-facilitated Exchange, a health insurance issuer that is offering QHP coverage through a Federally-facilitated Exchange or a State-based Exchange on the Federal platform must notify its enrollees of material plan or benefit display errors and the enrollees' eligibility for a special enrollment period, included in § 155.420(d)(12) of this subchapter, within 30 calendar days after being notified by a Federally-facilitated Exchange that the error has been fixed, if directed to do so by a Federally-facilitated Exchange.
45 C.F.R. §156.1256