The IRS has already announced that they have completed Form 1040X and stated electronic filing software companies should have this form available. Why don't you have it?

[bluedeb · Accepted solution]

According to TurboTax IRS forms availability, the amended form will be available in TurboTax on 3/25/21. 

https://care-cdn.prodsupportsite.a.intuit.com/forms-availability/turbotax_fed_online_individual.html

You can't file an amended return in TurboTax right now because the IRS has to approve their form that goes in the software so you can e-file.  You can get the 1040X form on the IRS if you want to manually enter your amended information & then mail it in.

To add:  The IRS right now is handling tax return processing since they only started accepting returns on 2/12/21.