Those advocating to not change anything in your return now are missing the bigger picture.
If I have a return e-filed and accepted and saved as My2020taxes.tax2020 I can open that up, check the e-filing status(s) all say Accepted and then save it as My2020Xtaxes.tax2020 and add in the missing W-2, EIP, 1099, etc as that is needed to manually complete a 1040-X from the IRS if the taxpayer wants to do that. It is their prerogative to manually file, e-file, etc.
By saving the return "as" another file you can safely open your original file when it's time to process the 1040-X as well if you choose to wait but there's nothing compelling you to not alter the accepted return, provided you save that as another file.
