We seem to be experiencing some intermittent connectivity issues which may be causing you to see some 503 errors. This is being caused by a service outage that is unfortunately outside our control. Once you're in a game you should be good, but if you're trying to see your campaigns or launch a game you may run into this issue. Your best bet is to try again a few minutes later, as the issue is intermittent. Sorry for the inconvenience and hopefully we'll be able to nail down the external cause of this and see if there are any ways we can mitigate it in the future.