Payment subscription - test callback

Question

We're currently looking at implementing Facebooks new subscription payments. We already have a working payment setup for Facebook, and the callback url is set correctly. If I make regular test payment the callback is called correctly.

The setup for testing subscriptions is according to this. But either if I choose the always success or always fail there is no callback made to the payments callback url.

It does return an object that says the subscription is active an has an ID.

{status: "active", subscription_id: 204626XXXXXX}

Answer 1

Is it possible you only get a request sent to the callback URL if the subscription state changes, and you already have an active subscription for the user? I would think you would get a client-side error in this case, but I don't see any evidence that there's an error code for that.

What happens if you make a regular test payment multiple times for the same account?