They are pretty good about updating the supported hardware page. But it's most likely the 1.2 note is because they can not support previous versions and can support later versions. Perhaps they are testing and will see this thread. @YiannisH_3CX - Can the Fanvil x6 be on hardware version 1.3 for 3cx?
We got the confirmation from the Fanvil team that the Hardware v1.3 is using the same FW as the v1.2 and fully compatible with the 3CX Phone System.
The appropriate guide is already updated