iOS 14: should IAP succeed or fail when re-purchasing auto-renewable subscription?

I am currently testing IAP of auto-renewable subscription with Sandbox account.

1. Purchase auto-renewable subscription

2. Purchase the subscription again during the period of validity.

3. SKPaymentTransactionStatePurchasing arrives

4. Popup appears "You are currently subscribed" with "Manage" and "OK" buttons.

So far this is common to iOS 13 and 14. However, when tapping the "OK" button, the flow continues with a different behavior as follow:

iOS 13:

• Purchase fails as SKPaymentTransactionStateFailed arrives with SKErrorPaymentCancelled

iOS 14:

• Purchase succeeds as SKPaymentTransactionStatePurchased arrives

This new behavior affects the code that I am writing so I need to confirm that this behavior was actually changed by design on iOS 14 and it's the expected one.

I found no documentation for such change, so any reference would be greatly appreciated.

It also would be interesting to know if anyone else detected this behavior and whether this behavior appears in production environment or only in test environment.