Does it support Apt-X? AAC is mentioned in spec sheet so I would assume its possible to get acceptable sound quality from iPhone, when using the Music app with

Does it support Apt-X? AAC is mentioned in spec sheet so I would assume its possible to get acceptable sound quality from iPhone, when using the Music app with AAC files, or even MP3 files. Anyone knows when using Spotify on iPhone and selecting bluetooth as output, will it use AAC then? or will it re-encode the sound from Spotify, either into AAC or, god forbid SBC?