The Internal Revenue Service took down its computer servers for scheduled maintenance last weekend, despite the fact that the tax-filing deadline for those who filed for extensions in April is at the end of this week.

The IRS has been experiencing glitches in its Modernized e-File system, which rejected nearly a quarter of the tax returns it processed during its first three weeks of operation this past tax season (see New IRS Software Rejected 23% of E-Filed Returns). Luckily, the agency is able to revert back to its tried and trusted older e-filing system when needed. The Associated Press reported Tuesday that tax prep processing giants like Intuit and H&R Block are able to default to the older system when the new one goes down. The IRS also gave plenty of notice about the scheduled holiday weekend shutdown, so it didn’t cause huge problems, according to the AP.

Only problem was that even after the scheduled shutdown was supposed to be over, the IRS still couldn’t bring the system back online until mid-Tuesday afternoon. And it’s not only the folks who took tax extensions and still didn’t manage to file their returns by the final Oct. 15 deadline who were affected.

This Friday is also the final deadline for the thousands of small nonprofits that still haven’t filed their “e-Postcards” after three years and are in jeopardy of losing their tax-exempt status. For those procrastinators who really did need those extra few days to finally file their Form 990-N or the 1040 they meant to file last April, they will need to finally get those filings done in the next two days. That is, while the system is still up and running.