Are PubSub connections limits enforced?

Under the “Handling connections failure” portion of the best practices, we recommend that you establish a new connection and listen to those topics before reconnecting.

You won’t get an error for that 11th connection if that’s what you’re asking. That could happen in the future, but it’s not currently the case. From a practical standpoint, a reasonable number of extra connections for reconnect purposes should be fine. Going way over the limits is a violation of our Developer Agreement.