Apparently, Apple doesn’t really want you to know this, but it’s hidden in plain sight, so here it goes! If you purchase a monthly Apple Music subscription for $10, or are an existing subscriber, you will be able to pay $99.00 for a 12-month subscription and save some cash. Counter- intuitively to the maximum, the option is buried within the App Store app, rather than the Music app.
Head there and go to the ‘Featured’ tab. Tap your Apple ID, enter your password, and tap ‘View Apple ID’. Then tap ‘Subscriptions’ and finally, there you have it – a 12-month Apple Music … – Source