Quest Guardian System

I'm curious if there is any information about the Quest Guardian system and how it will differ from the Rift.

I'm in the early stages of development for an experience where I will want to dynamically adjust the environment according to the players configured play space size.

Is it relatively safe to dive in developing with the Rift for now? Do we know if there are any fundamental differences with how the two guardian systems (Rift and Quest) will work?

Thanks! and sorry if this information exists elsewhere, I have tried digging around and haven't found anything.