The Centers for Medicare and Medicaid Services (CMS), which administers the health insurance marketplaces and regulates the provisions of the Affordable Care Act (ACA), on Friday threw down the gauntlet to President-elect Donald Trump and his incoming administration by issuing a final rule for the ACA for 2018 — setting its effective date three days prior to Trump’s swearing in.

Of course, any regulation issued since late May is subject to simple majority vote  kibosh by the House and Senate, both controlled by Republicans, under provisions of the Clinton-era Congressional Review Act (CRA).

Nonetheless, the ACA administrators seem undeterred by Trumpian threats to “repeal and replace” the ACA, or else they figure it doesn’t really matter. According to the notice published Friday, Dec. 16, in the Federal Register:

This final rule sets forth payment parameters and provisions related to the risk adjustment program; cost-sharing parameters and cost-sharing reductions; and user fees for Federally-facilitated Exchanges and State-based Exchanges on the Federal platform. It also provides additional guidance relating to standardized options; qualified health plans; consumer assistance tools; network adequacy; the Small Business Health Options Programs; stand-alone dental plans; fair health insurance premiums; guaranteed availability and guaranteed renewability; the medical loss ratio program; eligibility and enrollment; appeals; consumer operated and oriented plans; special enrollment periods; and other related topics.

Under Dates, the text stoically notes: “These regulations are effective January 17, 2017.” Donald Trump is slated to be sworn in on Jan. 20, 2017.