These packages are built against the current libmpdclient 2.16-1 from official Debian repository.
You can add deb.kaliko.me to your source list to follow future builds.
- Completely remove Sys V init support
- Add conflicts with mpd package
- Repository moved to non-backports
deb https://deb.kaliko.me/debian/ buster main
deb https://deb.kaliko.me/raspbian/ buster main
cf. dedicated page for more info on my debian repositories.