Delay auto-renewable subscription payment

Hello,

I have an auto-renewable subscription with a duration of 1 year and a free trial of 14 days.

Let's imagine a user that subscribes to this in-app purchase for the first time. After 14 days of free trial, he will be charged for the price of my subscription.

After 4 months, he invites a friend to the app. I want to reward him with 1 month of free subscription time.

Instead of the user being charged after 12 months after the first payment, can I make him pay only after 13 months after the first payment ?

And if I can, how can I do that? Do I need to use promo codes? or promotional offers? or another thing?

If I'm not being clear, feel free to ask me questions.

Kind regards

Delay auto-renewable subscription payment
 
 
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