@Critter-3
Yes, I know that the IL income tax forms aren’t yet finalized and can’t be filed yet. My original question was intended to point out the error in the hope that it’ll be fixed.
What I don’t understand is why this error is there, in the first place. The correct estimated-tax payment due dates — including the Jan. 18, 2022 due date (both federal and IL state) — have been known well in advance. However, in TurboTax Premier the IL Form 2210 (calculation of penalty for underpayment, which includes late payment) incorrectly shows a due date of Jan. 17, 2022.
