Apple Subscription Renewal(Server to Server Notification)

I always see a different latest_receipt value. If you use the latest_receipt_info info, you can use even an old latest_receipt value to call verifyReceipt URL and you'll get all the purchases. But if you use the field in_app (it seems that it is better to use the latest_receipt_info), you won't receive the last purchases if you use a old value of latest_receipt. When you call verifyReceipt, the response included in the in_app field seem to be the decoded value of the information stored in the latest_receipt. So, if you send an old value, you'll get a decoded value of old purchases. But in the latest_receipt_info you'll have all the purchases (well, the last hundred).

As a continuation of my previous answer... Even more, if you call several times to the verifyReceipt URL using the same value of latest_receipt, the values you get in the response, in unified_receipt.latest_receipt, will be diferent each time.