Renaming library folders when some albums have discs

Hey, I've been trying to rename my whole music collection to clean it up a bit. If I select a folder, press alt+5 and change the _DIRECTORY field to %year% - %album% then it works fine, if the album isn't multi-disc.

If the album has different discs, then it only renames 'disc 1' to the year and album instead of changing the folder name one level up.

Is there any way to get mp3tag to know which folder to rename in these nested folders?

Maybe this similar question and answer can help you to find the needed format string?

including the use of [] brackets:

It's not a bad try, but sadly a lot of my library has the %discnumber% field filled in, even if there aren't any other CD's (filled in as 1/1 or 1), so it'll try to do something on these folders too.

Also, this tends to just make a new folder, move only the music files, and leave the old folders behind along with cover art and scans, etc.

I'm not sure if mp3tag can really tell which folder is the name of the album that needs changing, and which folder is just "CD1"/"CD2"/"CD3" or "albums"/"live albums"/"singles"/"bonus content", etc. Would need something quite smart to know which is which I guess, as the folder that has the album name is anywhere between 1 to 4 layers deep in nested folders depending on the artist.