Yep, seeing same. (ST4 Build 2135, 9th Gen iPad, iOS 26.1.0)
Repro is simple.
- Go in History to clear Done Markers
- Create Playlist with 3 or more songs
- On each song in Playlist, set them to Autoplay
- Select first song in Playlist, then press Play
Observation:
As each song is played and playback moves to next song in playlist, DONE marker is applied to each song except the very first song in the Playlist.