My router came preinstalled with 6.2.0 and refuses to downgrade to 6.1.2. 6.3.0 installs fine.
The only reason I need 6.1.2. is that my device (Sprint Netgear Zing) is reported to only work with that firmware. I’ve got an open ticket and still waiting to see if they can either make the hotspot work with surf SOHO or allow me to downgrade to 6.1.2.
If anyone has some suggestions I’m all ears. WISP mode is not a option as I can already do that with any of my other routers that support WISP mode and save $180. Using the Surf SOHO will allow me to replace three wifi signals with just one (Hotspot - since it’ll be USB, TP Link 802 for WISP, and Asus AC66u for the better signal).