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I am working on an iOS app. I have created an annual offer code which is only eligible to new users and expired subscribers. May I know what will happen if an existing subscriber tries to redeem the offer using the offer code url? Then they would finish the whole process through the App Store. There are no ways for my app to block it. Would Apple not allow them to do this? If yes, would the existing subscribers have to cancel their subscription in order to redeem this annual offer code? If yes, will they then immediately see the offer? Or will they have to wait until their entitlement expires? Thanks.