The Form 1040X is expected to be available in the TurboTax software on March 25, 2021,
You can use the following link to check and find out when it is released for paper printing and e-filing:
TurboTax Expected Dates of Availability of federal forms
IRS is very busy right now with updating the American Rescue Plan into the IRS tax code, processing current year returns, sending out the Third Stimulus Checks and still processing 2019 paper returns.
If it will cause you to have a balance due, then you need to get it filed by May 17, the extended federal filing deadline so you can pay any additional balance due with it so you will not be penalized, but cannot file it until March 25 when the 1040X form is expected to be available.
If it will not change your refund or balance due on your federal and state returns, then it is not necessary to amend before the extended filing deadline of May 17.
