@Just-Lisa-Now- 

What is this EF Center that you mention in your post?  Is this something for Professional tax preparers, and not available to an individual tax preparer like me using Turbo Tax Premier? 

It is EXACTLY what I need to proceed with eFile'ing my 2021 Amended return.  I am getting an error on the signature date when I try to submit.  Can't add the current 2023 date, so try with the date I eFile'd the original 2021 taxes, and it gets kicked back during the validation stage of eFiling... would MUCH prefer to eFile versus mailing the 50-page thick printed 2021 Amended return.

appreciate any assistance you could provide!!