If you like your ACA plan, you very likely won't be renewing anyway

Sam Baker and  Jonathan Cohn have both spotlighted a Milliman briefing paper warning of an important potential glitch looming as the ACA's second Open Season approaches. It's this: while the government is encouraging current customers to renew their current plans via auto-enrollment, many customers may see significant price spikes if the plan they selected last year loses its status as a "benchmark" plan.

Subsidies are keyed to the second cheapest silver plan in each market, deemed the benchmark; subsidized customers who buy a plan more expensive than the benchmark have to pay the whole difference. Thus, if the ACA affordability formula decrees that you should pay $30 per month for a benchmark plan with a base premium of $300, and that plan's premium spikes to $350 and it cedes its benchmark status, you'll now be on the hook for $80 per month rather than $30 if you stick with it. To stay at roughly the $30 level, you'll have to switch to one of the two cheapest silver plans on offer this year. (Additionally, if the benchmark plan price goes up, customers' advanced premiums may also go up if they re-apply rather than auto-enroll.)

I wouldn't dream of downplaying this very important potential glitch. But I think it's worth noting an often-unnoticed market factor that will mitigate its impact somewhat: there's tremendous churn in the individual market, and it's likely that half or more of those who enrolled in private plans in 2014 will be looking to renew. Many will have found jobs that offer insurance; some will become eligible for Medicaid; some will marry or move and need to select a new plan in any case. In November 2013, healthcare scholars Rick Curtis and John Graves estimated (with some caveats) that just 42 percent of Americans eligible for subsidized exchange coverage at end of 2014 (i.e., the upcoming open enrollment season) were eligible in the prior year. That doesn't quite tell us what percentage of those currently enrolled in subsidized exchange plans will not be seeking coverage for 2015, but it gives an idea of the degree of turnover.

Yes, Peter Suderman, the ACA covers the short-term as well as long-term uninisured.

Many people poring over the data still emerging from the ACA's first open enrollment season seem not to grasp  the volatility of Americans' insurance status.  Take Peter Suderman:

Kaiser’s survey finds that the majority of previously uninsured lacked coverage for two years, and that 45 percent reported not having coverage for five years. Which means that more than half of the previously uninsured were covered at some relatively recent point.

Now, many of those people clearly were having difficulty getting coverage for some reason—perhaps as a ripple effect of the recession, perhaps because of some other factor. But many of them appear not to be completely uninsurable. These are not people who couldn’t get insurance under any circumstance. They’re people who didn’t have it for the last several years.

Obamacare’s supporters would no doubt say that the law was designed to help those people just as much as it was designed to help those who never had coverage at all. That’s an entirely reasonable position. But when we talk about Obamacare’s coverage effects, it’s important to be clear about who is being covered: a sizable number of people who were already insured, as well as people who were both eligible for coverage and covered at one point, but had lost their coverage.

It's true that the ACA is designed to help the long-term uninsured. It's also designed to help the millions who fall out of and back into insured status every year. Last fall, healthcare scholars Rick Curtis and John Graves brought those millions into focus:

ACA signup: it ain't over when it's over

[Update, 3/26: Yesterday's announcement that a "special enrollment period" will be granted to anyone who claims s/he tried to enroll before 3/31 underscores the year-round fluidity of enrollment outlined below.]

Anyone who's paying attention knows that March 31 is the open enrollment deadline. After that date, you can't "get covered" for 2014.

Unless, that is, you qualify for Medicaid -- or experience a "qualifying life event" such as a job loss or divorce or childbirth. That's a lot of people.

Roll on, Medicaid, roll on

Medicaid enrollment is continuous. State agencies and private-sector partners work year-round to get kids enrolled in CHIP.  Adults newly eligible in states that have enacted the ACA's Medicaid expansion can enroll year-round too. Enrollment won't be possible through Healthcare.gov, but individuals can apply through conventional channels, and nonprofits working to enroll the uninsured will continue their outreach after 3/31.