If your bottom line changed from a balance due to refund or reverse then the mailing address would have changed and amended returns go to yet other addresses.
https://www.irs.gov/filing/where-to-file-paper-tax-returns-with-or-without-a-payment
Now for the "NON filer" notation ... this simply means your return has not yet been entered into the system ... once it is in the pipeline you will see progress on the WMR? tool. The IRS is way behind in processing returns this year so all you can do is wait.
