We had some issues with our subscriber client where our endpoint was often inaccessible to the appspot hub causing a high error rate. These issues have been fixed and the error rate is now very low, however we haven't been receiving verification messages from the appspot hub for any new subscription requests.
We are making asynchronous subscription requests and are receiving a 202 messages from the hub however the verification request containing the challenge parameter and expiry is never coming into our subscriber client. We are still receiving feed updates from our current subscriptions but cannot seem to make any new subscriptions or re- subscribe to expired ones. We are not having any subscription issues with other hubs but appspot seems to be an issue. Is it possible we were blocked from making new subscription requests due to high failure rate at our endpoint?
