Here's how it should work .
After you click AMEND, Turbotax sets up the 1040x.
Then revise your tax return to be correct.
The differences will flow to 1040x.
When done, print the 1040x.
It is up to you to find the forms and schedules that changed due to your amendment.
Those are the ones to be included with the 1040x you file.
It's also up to you to verify that the 1040x reflects all the changes properly before sending..
