Hello, I am a backend developer currently handling Apple's auto-renewable subscriptions. I have two different products in the same subscription group, one is a monthly subscription, and the other is a quarterly subscription, with the quarterly subscription having a higher priority than the monthly one. Currently, I subscribed to the monthly plan in the sandbox environment and then upgraded to the quarterly plan. I only received an UPGRADE notification. I would like to confirm whether this is the only notification I should expect, or should I receive an upgrade notification, a subscription notification for the quarterly plan, and a refund notification for the monthly plan?