NOTHING can be efiled right now at all ... the IRS has shut down all efiling for the switch to the 2020 programming. Now WHEN the efile system opens up in mid to late January it is still not known if the TT system will allow efiling of prior year returns like the professional programs can do. Since this is brand new we all have to take a wait and see position.
If you already mailed in an amended return the IRS says to NOT mail/file it again as that will only mess you up more and delay the process further : https://www.irs.gov/filing/wheres-my-amended-return
