45 C.F.R. § 156.1010
(f) For cases received from HHS, QHP issuers operating in a Federally-facilitated Exchange are required to notify complainants regarding the disposition of the as soon as possible upon resolution of the case, but in no event later than three (3) business days after the case is resolved.
(g) For cases received from HHS, QHP issuers operating in a Federally-facilitated Exchange must use the casework tracking system developed by HHS, or other means as determined by HHS, to document the following: