Thanks everyone. It's doing my head in this error...
I've logged a ticket with Cloudflare and our host today - the issue seems pretty widespread;
Though, I'm still pretty certain that this;
... resolves the issue.
I'm reasonably sure people who are saying it hasn't, aren't clearing their cache properly. You need to double check you're clearing the device cache - remembering
Chrome has profiles, different profiles have different cache. Its something you should do fairly regularly anyway? I've just dug out an old device which I knew had the problem for one Chrome profile to demonstrate;
I say reasonably sure, as I'm only going by my own experience and most people I've told to clear the cache report the issue to immediately resolve.