Sometime this week I suddenly lost static playlists in my Music (née iTunes( Library. The last static playlist in my list is "MP3 Releases", but I previously had additional playlists such as "Music to Test Speakers With", and various other random names I've already forgotten, but nevertheless are alphabetically after MP*. It appears that all of them before that are present, but none after. This only appears to have affected Static Playlists, no Smart playlists nor Apple Music playlists, nor any other individual song entries that I have noticed yet.
I have multiple computers, all leveraging iCloud Music with an Apple Music subscription, iTunes Match and possibly something else I'm forgetting also mixes in there as well.
I noticed they had disappeared from my Desktop (Windows, iTunes whatever is latest from the Microsoft Store), I opened Music.app on my iPhone (iOS 13.3) and they were also gone. My laptop is my "source of truth" for my music library, I do all my tagging, converting, organizing, and principle storage here. Just prior to writing this I opened Music.app (Catalina, 10.15.3β) and they were initially there, but only for a few seconds until the sync caught up and deleted them, I didn't have the presence of mind to click, screenshot, click, screenshot, etc.
Is there a way to retrieve them via some means? Somehow revert the library at least temporarily?
In ~/Music/Music there is only "Music Library.musiclibrary", in ~/Music/iTunes I do have a "Previous iTunes Libraries" folder, but the most recent one is dated 2018, likely too old for a majority of those playlists, certainly the more recent ones I care about. Anything pre-Catalina GA is likely too old for some (though maybe not all).
I do use Time Machine, but I'm wary about resurrecting the Music Library.musiclibrary file and causing who knows what other organizational nightmare, but perhaps it would be worth it to do so and read some index file that has playlist metadata?
Is there any guide to doing this? Or saner means?