This was an unscheduled outage which occurred at circa UTC 2019-10-21 03:50 and was resolved at UTC 2019-10-21 04:05. The root cause of this issue was a misconfiguration in our infrastructure which meant unexpected load was placed on our servers. Since the servers became unresponsive during the incident, logs of usage are not available during that time so user impact cannot be specifically quantified.
Our server configuration has been updated to prevent recurrence of this type of issue in the future. We apologise for any inconvenience. We are continuing to monitor the application closely to see ensure the changes we have made are effective.