They aren't supporting Roon out of the box...
They are simply Roon end points - meaning they will turn up as available speakers when you use the Roon software. Remember, this isn't special to B&W, any product with Airplay, Airplay 2 or Google Cast audio is a Roon end-point capable product.
Effectively they have no streaming via their app, they just have Spotify Connect, Bluetooth and Airplay 2... adding streaming services appears to be their plan for the future, until then purchasers need to be aware that they won't be getting much in the way of 'special sauce', just B&W speakers and a new mesh network.
The mesh network is the real piece of interesting tech, how well it works is going to be the making or breaking of the product. I guess this is where B&W will have put a majority of their resources during development.