IF you have paid an annual Apple Music subscription and switch to Apple one, especially at the beginning of the renewal, do you get a refund on the annual subscription or a discount on the monthly Apple One subscription, or just end up overpaying for both?
Step 4 of:
Bundle Apple subscriptions with Apple One - Apple Support
simply says "If you already subscribe to Apple Music, Apple News+, Apple Arcade, or Apple TV+, you don't need to cancel those subscriptions. They will automatically be canceled when you're billed for Apple One." It does not says whether or not the balance of an annual plan will be refunded. I suggest you use the "Get Support" link at the top-right corner of this page to find out.
Switching from Apple Music annual subscription to Apple One
