Why does Recently Added in Apple Music on iOS and CarPlay list old playlists and not recently added songs?

Just in case anyone's also frustrated by this situation (e.g. when syncing your library to a new phone), this rather convoluted process worked:

1. I chose a historical date that was before the 60th "most recently added" album in my collection. (Bearing in mind that the Recently Added list is 60 albums/playlists).
2. I changed the date on my computer to this date. (I don't think that this step actually matters, but I did it anyway).
3. I put my phone into airplane mode and disconnected from wi-fi (just to avoid any possible on-line date/time checking), and then manually changed my phone's date to the same historical date. (Settings/General/Date & Time/Set Automatically = Off)
4. In my iTunes collection I unticked the 60 "recent" albums that I'd expect to be displayed in the Recently Added list (i.e. the albums that should be there if the random playlists weren't automatically displayed). I also chose to only sync ticked songs, and then performed a complete resync of my phone.
5. (I think - but it's just a guess - that now the library on my phone thinks the playlists etc were added on the made up, historical date from step 1).
6. I reconnected devices to the internet, and corrected the dates on both (computer and phone).
7. I re-ticked the songs from the 60 albums in iTunes, so that my entire collection was once again "ticked".
8. I performed another sync, that now included the songs from those 60 albums.

The Recently Added section finally shows the correct 60 albums again!

So far I haven't figured out a logical pattern, or come up with a date-based theory that helps me work around it.

There is no option to customise, including sort, the "Recently Added" section of the Library home page. The rules appear to be inbuilt to the iOS/CarPlay app.

Before I completely re-synced my library with the iTunes/Apple Music library on my computer, the list correctly showed all recently added songs/albums (I'd expect this to be based on the "Date Added" tag) and any Playlists I had recently created. (The list is 60 "albums"/playlists long).

After the full re-sync, the Recently Added section displays 60 Playlists only, and none of my genuine recently added items are shown anymore. They appear to be displayed in a random order (i.e. they aren't sequenced by the date the playlists were created).

If I remove an album from my computer's library, re-add it and then sync, it will be correctly shown as "Recently Added". But doing this loses meta-data such as Rating, Playcount, Last Played Date and (the correct) Date Added. FIxing that for 60 albums is time-consuming.

If I remove albums from the sync itself (i.e. sync only selected tracks), remove them from my phone by re-syncing, then switch back to syncing them again, it has no affect. Even though they were recently added to the iPhone itself they do not display in this list.

Understanding how the iPhone sync rules worked might help figure out a work-around.