Outdated Itunes Library .itl file.

So...

I recently lost all of my playlists and music on my music app. I followed some advice on here and opened the library from an older, uncorrupted source. That worked a treat. The only problwm is the most recent library I could find was from October 2019! I use time machine to back up my computer weekly but it seemed for some reason, the library file it was using was never updating.

So I'm now in the process on manually adding all of the lost music and rebuilding playlists - luckily the music is still in my itunes media file and my ipod still has all the playlist info. But should it corrupt again I'd like an up to date library file I can restore from.

How do I go about creating this? I would have though the music app automatically saves new additions to the library but seemingly not....

thanks a bunch in advance