InfoPath Dev

I am having problems keeping existing forms from being updated when I make updates to the template file. I have a Sharepoint site set up for time sheets. From time to time changes need to be made to the template file. The problem is I don't want it to effect forms that have already been filled out.

Before I save the changes and publish the template, I go to Tools > Form Options > Advanced. Then for "On Version Upgrade:" I have "Do Nothing (existing forms might not work properly."

Yet every time I make a change to the template, all forms that have already been filled out, now show the changes I just made. Any idea what is going on here?

Are you seeing the changes in the UI or the fields(schema changes) that you have added newly?
If it is UI then it will show the new UI. Fields that will not get added. Even if you see the fields in the UI they will all be disabled.

Yes, I'm seeing it in the UI. For example, I removed the graphic along the top of the page and saved the template. The forms that were already filled out then reflected that change despite me selecting "Do Not Update" in the form options.

So whatever changes that occur in the UI will always be updated, eventhough I selected Do Not Update? If that is true, do you have any idea how I can version the template so old forms are untouched? In my case they would need to remain in the same document library. My supervisor would like to not have to archive them into a seperate folder.

Thank you for your help.