I'm in a similar situation. In my case a late mailed form that had been entirely forgotten about arrived the day after filing. This is so frustrating! Using the link that MichelleLOposted posted in their earlier answer, as of right now it appears Form 1040X, Amended U.S. Individual Income Tax Return is scheduled to be available 03/17/2022 for both print and e-file on all listed TurboTax products.
At the very least, it would be nice if the TurboTax application either stated this date or provided the relevant link on the screen instead of just saying "check back soon" as it does now.
