MarsSeed [1] filed a request to merge subsonic-beta [2] into subsonic [3]: The beta is the same version as the stable package, and there's no new release since 2019.
[1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/subsonic-beta/ [3] https://aur.archlinux.org/pkgbase/subsonic/
