I went from 1.2.0 to 1.2.1. Release notes mentioned not being able to downgrade below 1.2.0. I was not having luck with the upgrade either at first. I did factory reset, format card in goggles, copied over firmware. I believe I may have not been waiting long enough for it to start. It took about 45 seconds after powering on the googles before the update started when it worked.