Form 1040X, Amended U.S. Individual Income Tax Return is estimated to be available on 02/27/2020
https://care-cdn.prodsupportsite.a.intuit.com/forms-availability/turbotax_fed_online_individual.html
According to the TurboTax Federal forms availability forms list, the amended form (1040X) will not be available until 2/27/20.
