Multiple Bowers and Wilkins speakers on Airplay IOS

[Rugbyboyle]

I use a Bowers and Wilkings A5 to play Spotify via Airplay.

I am thinking of buying another for the kitchen and assumed I could play through both speakers and toggle one or the other off/on like on Sonos. Bowers and Wilkins have informed me this is not possible as their hardware will not support Airplay 2 and it is currently not possibly on normal Airplay.

Is there a solution to this?

I believe there is an app which can do this but I cannot find it.