After uploading a support document, each time you do an edit a new version is created. This also allows you to restore to all previous versions of the document by using the version history found at the bottom of the supporting document. 

To restore to a previous version of a supporting document;

1, Locate and enter the supporting document in the Working Paper Index;

2. Scroll down to the Workpaper History section underneath the preview screen:

3. Click the "Restore this version" button the right of the version you wish to restore: