Hello - If a Schedule C 1040 has been filed already, is it possible to make a retroactive s-corp election and amend the 1040, filing an 1120S as well for 2021? Also brings the question of whether there was payroll with timely tax deposits, but what if there wasn't? Does that void the election? Maybe it would be better to elect for 2023 if that was the case...?

Any help is appreciated. Thanks.