So what can Republicans do to make changes to system in as orderly a way as possible?

They should agree that whatever else is in their upcoming Obamacare bill, that it include one measure: a provision to freeze new enrollment in Obamacare. That is, they could continue allowing those who have benefits to receive them, but then prevent anybody from enrolling in the law’s expanded Medicaid program who was not already on the books as of the date the bill is signed into law. Additionally, nobody would be eligible for subsidies for Obamacare’s exchanges who did not already sign up for coverage by Jan. 31 — the last date of open enrollment for this year.

The current preferred approach of repealing much of Obamacare on paper, and then delaying the implementation of that repeal, creates a multitude of problems. One of them is that the program would be enrolling millions of new people into a system that is about to go away, meaning more people will be disrupted the longer Republicans wait. Even if Republicans were to limit a delay to under two years (that is, make the effective date Jan. 1, 2019) that would mean additional open enrollment cycles for the exchanges this fall and in the fall of 2018, let alone continued Medicaid enrollment.

It would also create an “Obamacare cliff” — a date at which subsidies would be cut off suddenly.