@zaach - AFAIK, neither the auth-server nor the fxa-js-client return the 201 if the service is unavailable, we assume it [here](https://github.com/mozilla/fxa-content-server/blob/c6f5db2311ea8520aaa1baccf7ff3392504dfbc6/app/scripts/lib/auth-errors.js#L96). If that is the case, we could change `SERVICE_UNAVAILABLE` to another number and use `201` for `SERVER_BUSY`