While I understand that streaming rights to content or not will fluctuate, it is inconvenient to your users to manually search each day for these grayed out tracks.
Please have those tracks, whether in playlists or "Your Music" moved to a "Currently Unavailable to Stream" playlist so that those spots would free up in the 10,000 song "Your Music" cap.
The app could check that playlist upon startup and, if status has changed for any since last use, popup a "Some of your formerly unavailable content is available again to stream" message allowing you to add them to other playlists or "Your Music" again (once you delete to below the cap).
Updated on 2020-03-20
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