Is there a new manual on how to publish app to google play?
since I see there is new app signing method, and I cannot seem to pass this part using old way
Once you Confirm app signing, you can't get rid of it.
You can "Opt Out" and upload the APK as you previously did.
I made the mistake, at first, of confirming app signing. I had to go back to the "All Applications" page, delete the app, then re-create, and made sure to select Opt Out when I uploaded the APK.