How to restore Apple Music media library after subscription lapse?

My understanding is that if you end an Apple Music subscription, or let it lapse,

• All "offline listening" copies of subscription songs are removed, or stop working.
• All playlists containing subscription songs are removed, or stop working.
• All copies of music "synced" by "Sync Library" are removed, or stop working (excluding the one on the original device).
• This happens right away.

if your offline listening copies and playlists have disappeared, and you want them back, you will probably need to re-download songs, and re-create playlists, manually.