We're investigating intermittent connectivity issues to the Onyx platform at present, we'll update as soon as possible.
Update 12:40BST: We've isolated the issue to one cluster within the Onyx platform, so a subset of sites might still be experiencing intermittent performance issues - the majority of Onyx sites should now be back up and running normally, and we're continuing to work on the affected cluster.
Update 13:40BST: We've identified that the load issues experienced are related to a DDoS attack against one site. Mitigation is now in place, and sites on the affected cluster are now also back to full speed. We're continuing to monitor.