under section 107(c) and establishing a Roth HSA for such residents who do not have a Roth HSA unless the resident has affirmatively elected not to be so enrolled and not to have a Roth HSA, respectively. Any such enrollment under this paragraph shall be coordinated with the annual open enrollment periods provided under section 107(b). (d) Risk mitigation mechanisms and reinsurance and risk-Corridor programs (1) In general Notwithstanding any other provision of this title or section 223(c)(2) of the Internal Revenue Code of 1986, a State may establish— (A) mechanisms for risk mitigation or risk adjustment in order to limit volatility in the premiums based on health experience to class-average premiums