If you own multiple Apple devices, or even Windows or Android devices, you can sync your Apple Music library across all of them. Here's how.

If you are using a Microsoft Account to sign in to your Windows devices, the operating system synchronizes your preferences across all the devices you use. However, you may want to disable this ...

After moving the unsynced files out, turn on syncing again by clicking the OneDrive icon on the taskbar and heading over to the gear icon > Resume syncing. Wait for the sync to finish.

However, you can turn on cloud backup for the Timeline feature. It is not enabled by default and must be manually turned on, which will also allow Timeline syncing.