We are currently investigating reverse proxies instabilities on our Paris zone.
EDIT 18:56 UTC: To be more specific about the instabilities, the connections were slower to be processed, increasing the response time, sometimes drastically. The root cause has been found and fixed at 18:42 UTC. Since then, everything is back to normal. We continue to monitor the situation.
EDIT 19:11 UTC: Additional investigation will be performed to pinpoint the exact cause of the problem and measures will be added to prevent it from happening again. Sorry for the inconvenience.