I've been unable to find much more information either - and I've looked on several occasions. It looks like it's really up to app developers whether or not they will implement this, even if this gets rolled out to all Android phones on v14 eventually. No guarantees that Spotify (or Apple Music, or Amazon, etc) will actually add bit perfect playback to their Android apps if it is technically possible.
I've been unable to find much more information either - and I've looked on several occasions. It looks like it's really up to app developers whether or not they will implement this, even if this gets rolled out to all Android phones on v14 eventually. No guarantees that Spotify (or Apple Music, or Amazon, etc) will actually add bit perfect playback to their Android apps if it is technically possible.
Here's hoping though, it would be really great.