This sounds like it could be the well-known bug with Spotify Connect, where only the first 100 songs in any given playback context are submitted to the queue[1]

This sounds like it could be the well-known bug with Spotify Connect, where only the first 100 songs in any given playback context are submitted to the queue[1]. This particular bug has been around since at least 2016. [1] https://community.spotify.com/t5/Other-Partners-Web-Player-etc/BUG-Spotify-Connect-only-shuffles-100-songs/td-p/1299418 https://community.spotify.com/t5/Other-Partners-Web-Player-e...