SONOS is deprecating the unofficial UPnP control for most operations, for all S2 devices. It is not a one-off kill switch, but slowly through updates, less features will be available through the UPnP interface. Instead they are moving towards a proper HTTP API, which is already online. However for now they have only officially launched the cloud based API, when later opening for the LAN based API. The LAN based API does exist, but is not open to anyone else than certified “works with Sonos” partners, yet.
Good news is though, that integration using the public cloud based API is free, as long as you registers. This opens for the possibility that a new SONOS binding can be made, using just a standard REST binding, but each SONOS owner will need to register as a developer, to get their own API key.
Bad news is that already now, some SONOS equipment does not show playbackmedia data, like title, artist and albumcoverart over UPnP. An actual example is the SONOS beam gen 2.
For those who are privacy oriented - and especially the SONOS customers outside of US - will wait to integrate SONOS, until there is a working LAN binding, to not allow US cloud based access to builtin microphones in our private homes. But that LAN binding WILL come at some point.