The service will be interrupted because the services are two difference store countries. Your Apple Music playlists will be lost and you should download all purchases since there is no guarantee they will be available from the new country's store. Read the support article for details regarding what happens when you change country. Personally I would also make backup copies of everything in iCloud too since in theory it too is lost.
"Redownload your apps, music, movies, TV shows, and books on any devices that you might use to play or read them in the future. Some types of content might not be available in your new country or region. (Learn what types of content and services are available in your new country or region. - Availability of Apple Media Services - Apple Support )"
In the legal documents: Legal - Apple Media Services - Apple you will find, "When your Paid Subscription to any Service ends, you will lose access to any functionality or Content of that Service that requires a Paid Subscription."