Set HomePod default music streaming service to Amazon Music

Like I’m sure many people I subscribe to a few different streaming service like Spotify, Amazon Music, Soundcloud, etc…. When I interface with my HomePod speakers I want them to play Amazon Music by default without going through my iOS device. I would like to use the other music platforms for different reasons at different times, but for the HomePod Speakers I want them to always default to Amazon Music. In the past it was possible to set the default but that is no longer true. How do we set default music streaming service for HomePod speakers? If it’s not possible, I wonder if Apple will address it.