We have added measures to handle this case if it happens again, however it seems Keen.io's API is back to normal throughput and responding in a timely fashion. We are looking at ways of improving this to avoid any increases in latency (loading times) if this happens again in future. Sorry for the inconvenience.
Partial fix in place, sites are loading again, but still slow due to 3rd party timing out.
Working on a workaround
One of our 3rd party providers who we use for tracking pageviews is currently timing out and it's slowing our loading of our store fronts.