Smart Playlists and Apple Music

I have a playlist of around 300 unordered songs, all added from Apple Music, which I'm slowly trying to move into a new, ordered playlist. To avoid duplicates, I created a smart playlist called "To Be Ordered", with the rules set as "Playlist is [unordered playlist]" and "Playlist is not [ordered playlist]".

For some reason with nothing in the ordered playlist yet, the smart list is only finding 80 of the 300 songs. It also has the icon next to it saying it "cannot be added to your iCloud music library".

Any ideas?