Downloading music to Apple Watch is broken

This is for an iPhone 14 Pro IOS 17.4 and Watch Ultra on software version 10.4 after the recent update to 17.4.

Downloading music to the watch is now broken. This is after many hours investigating the issue I am about to describe, involving multiple factory resets of the phone and the watch.

Before doing anything whatsoever (no music yet on the watch, the watch has been reset, and the phone has been restored from a backup), when entering the music section of the watch app on the phone, the "Recent Music" option is selected (by default) and it is attempting to download some random album from (I think) the recently added list of the phone. In my case, it is a 10CC album. If I rewind and delete the 10CC album from the phone, it picks another album.

The 10CC album is actually now on the watch, and will play.

If I then download another album that I select myself using the "Add Music" option, it appears to perform the download. It is listed in the "Home" section on the watch (it used to be called "Downloads" so this is a change in functionality) and can be selected to play.

But here is the real problem. It plays the 10CC album! I can then download another album. Select it on the watch - it plays the 10CC album!

It is comprehensively broken. Furthermore, if I delete all music from the watch, it will still play the 10CC album. It never disappears.

Cmon, Apple, sort yourselves out. Don't you ever test software after a major change like this?

Please can someone try this and report back. I cannot believe that it will only be me having this issue.