Republican leaders in Congress are in no hurry to pass a bill to address the fate of the 690,000 unauthorized immigrants who were protected from deportation and allowed to work in the US under the Deferred Action for Childhood Arrivals (DACA) program, which the Trump administration announced in September it was bringing to an end.

Their reasoning is simple. The Trump administration named March 5 as the end date for DACA — meaning Congress still has four more months to work something out. “I don’t think we should put artificial deadlines inside the one we already have,” Speaker Paul Ryan (R-WI) told reporters Thursday.

One problem. The March 5 deadline really is artificial — it doesn’t actually mark the date when immigrants will start losing their DACA protections. That is, as far as anyone can tell, already happening. And it’s only going to accelerate over the next several months.

By March 5, 22,000 immigrants will have lost DACA protections because their applications for one last renewal weren’t received at government offices by October 5, a deadline that the Trump administration set only a month in advance, and didn’t notify immigrants about.

Many of those immigrants simply missed the application deadline. But others, it’s now becoming clear, submitted their applications before the deadline — sometimes weeks before — and were the victim of a mysterious mail screw-up.

As Liz Robbins reports for the New York Times, renewal applications from 33 DACA recipients in New York and 21 in Chicago were sent well in advance of the October 5 deadline — only to get stuck in limbo somewhere around the US Citizenship and Immigration Services processing center in Chicago. In one case:

Tracking data from the United States Postal Service shows the envelope arriving in Chicago on Sept. 16 on its way to the regional processing warehouse of the United States Citizenship and Immigration Services, the agency that administers the program known as DACA. Then the packet started circling Chicago in a mysterious holding pattern. From Sept. 17 to Sept. 19, it was “in transit to destination.” Then its tracking whereabouts disappeared until Oct. 4. Once again, it was “on its way.” On Oct. 6, a day too late, it was delivered.

The mail-error revelations make it crystal-clear that if Congress really wants to protect DACA recipients from deportation en masse, they can’t wait until March 5 to do it. And if they do, they’ll be allowing some immigrants to fall through the cracks.

DHS told Congress it had until March 5 — but it didn’t give DACA recipients that long

The Trump administration’s plan to end DACA had three parts.

It stopped accepting new applications for protection (from people who had just become eligible for DACA, for example by turning 15, or who had only just managed to get the $495 fee and documentation together) on September 5.

It announced that it wouldn’t be allowing any DACA recipient to renew their protections (which expire after two years) if their current grant of protection and work permit expired at any time after March 5, 2018.

And it gave the 154,000 immigrants who currently had DACA, but whose protections were set to expire before March 5, one last chance for a two-year renewal — but only if they got their applications in by October 5, 2017.

DHS didn’t notify immigrants that they only had a month to get in their DACA renewals. (When the program was in effect, immigrants were told to file for renewal about three months in advance of the expiration date.) Advocates spent a month sprinting to notify as many immigrants, and compile as many applications, as possible. (The New Yorker’s Jonathan Blitzer reports that the memo setting that deadline was written by Gene Hamilton, who helped write immigration policy for the Trump campaign and transition team and is now reunited with former boss Jeff Sessions at the Department of Justice.)

In the end, 132,000 applications came in on time — including nearly 20,000 in the final day of the window, and an additional 13,000 in the two days before that. But 22,000 people hadn’t gotten their applications in to a USCIS office by the deadline — dooming them to lose their protections when the date on their current work permits expired.

If you assume a constant rate of DACA losses, according to the Center for American Progress, that means 122 immigrants have lost their work permits every day since September 5 — nearly 8,000 by the time Paul Ryan waved off “artificial deadlines” on November 9.

The real number is probably lower than that. Immigrants who were set to lose DACA in 2017 are more likely to have applied by the deadline, because they would have done so in any case, than immigrants who were set to lose DACA in 2018.

But if fewer than 122 people are losing their DACA protections a day right now, that means more than 122 will be losing their DACA protections every day as we approach the March 5 “deadline.” Congress could mitigate the disruption by passing a bill now rather than waiting until March — but the closer it gets to March, the more immigrants will be vulnerable to deportation while Congress debates how to protect them.

The mail snafu means that immigrants who tried to follow the Trump administration’s rules are being punished

It would be one thing if members of Congress took the position that they didn’t need to find a DACA fix before March 5 because anyone who lost protections before then had only themselves to blame. They could say that DHS set a deadline, and people who didn’t meet the deadline don’t deserve as much sympathy as the people whose DACA will expire after March 5 who never had a chance to renew.

The mail snafu blows away that argument. It makes it clear that at least some DACA applicants who thought they were renewing in time and following the rules are being left out in the cold.

DHS was very clear that it wouldn’t accept any application that wasn’t physically in a USCIS office by October 5 — even if it was postmarked earlier. But some of the immigrants subject to the Chicago mail snafu applied in mid-September — as early as September 14, more than three weeks before the deadline. They had no reason to believe, when they mailed their applications, that the applications wouldn’t be received in time. But they weren’t.

The Post Office has taken responsibility for the snafu: A spokesperson told the Times’ Robbins that an “unintentional temporary mail processing delay in the Chicago area” had caused the delays. This raises the possibility that more than 54 DACA recipients were affected, though it doesn’t explain why applicants in New York and Chicago experienced problems while those in Philadelphia and Boston (which were sending applications to the same office) were not.

DHS secretary nominee Kirstjen Nielsen, during her nomination hearing in the Senate Judiciary Committee Wednesday, said that the department might reconsider its stance toward DACA applicants who’d missed the deadline due to circumstances beyond their control — like the hurricanes that hit Texas and Florida in September.

But the department has said it’s not going to reconsider the applications delayed by the post office snafu. (It cites regulations that set the receipt date as the deadline, but advocates point to past cases in which the government extended the deadline at the last minute because it had gotten an unexpectedly large number of applications at once and wanted to make sure they were all processed.)

Even if DHS’s hands are tied, it didn’t have to set the October 5 deadline to begin with. And it certainly didn’t have to give 150,000 immigrants an October 5 deadline for DACA, then tell Congress that the deadline for them to act on DACA was March 5.

It was inevitable that immigrants would fall through the cracks. We now know they have, for reasons outside their control. Congress’s desire to carefully deliberate a solution for DACA recipients makes sense — but they ought to at least be aware that their deliberate pace has consequences for some of the very people they’re trying to protect.