How do I amend an amended return in Pro Connect when I didn't prepare either the original or the amended return?  

I have 3 amended returns for 2016-2018 that were prepared by someone else.  I am asked to enter the information in Pro Connect and then amend the amended return.  

Normally I prepare a return, submit it and then after it is accepted and I need to amend it, I do so.

Here I will only be submitting it once and wasn't quite sure how that works.

Titus