How do I amend an amended return?

[davidcaruso77]

I have an amended return that I need to amend.  Based on instructions I've read on this site I've done the following:

Open the amended return, duplicate, delete the 1040X form, save and close.

When I re-open everything looks good.  The numbers match the amended return.  However, when I try to amend this return the numbers from Column A revert back to the original return.   How do I get the amended return to be the starting point for my new changes.

[Critter]

Make a duplicate but do NOT remove the 1040X ... just click on amend a return again. Then look at the 1040X and the amended figures should be in column A.