The IRS hasn't announced their annual e-file closure or reopening date yet, but typically when individual e-file reopens in January or early February, you can still e-file the currently due year and two prior. 

So we expect that near the end of January, TY22 e-filing will open, and at that time you'll still be able to e-file TY21 and TY20 returns, including those for whom the due date was extended due to Ian.

Rebecca