I’m out of ideas. I tried SPFlash in Windows with different settings and lost my IMEIs. I restored them and then tried just using fastboot and again lost my IMEIS. I restored them and now have Ubuntu Touch installed.
I think the only way to get back to Android from UT will involve wiping your IMEIs. Write them down first with your Serial Number!
In order for SN Writer to work properly in Windows, u must do the format option.
I started a Windows thread of what I did: