What does promotional_offer_id refer to when I use one-time promto code?

Hi, I'd like to implement a feature to integrate with the IAP promotion code.

I generated a one-time promotion code and redeemed it. I find the receipt from Apple store contains "promotional_offer_id".

I am wondering what it refers to? Its value is not equal to the redeem code, but it is like a UUID.

Does anyone have ideas?

What does promotional_offer_id refer to when I use one-time promto code?
 
 
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