Upgrade vs Downgrade Subscription

We're in the process of implementing in-app purchases and I'm curious if someone can provide more detail on how Apple defines an "Upgrade" vs. a "Downgrade" when a user makes a change to their subscription. An Upgrade goes into effect immediately, but a Downgrade goes into effect at the next renewal.

So is an Upgrade if the user changes to a longer duration of a subscription plan and Downgrade is if a user changes to a shorter duration of a subscription plan?

For those still struggling with this question: upgrades and downgrades are based on how you define the 'levels' within a group. Moving from a subscription with a lower level to a higher level (1 being the highest level) will trigger an upgrade, whereas moving from a higher level to a lower level will result in a downgrade.

For more information check the section 'Ranking subscriptions within a group' here.

Upgrade vs Downgrade Subscription
 
 
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