I've deleted and recreated and it still didn't work. I'll try to do that again tomorrow but it's really frustrating me
So, strangely, logged on this morning and looked in the error folders and nothing untowards. When i looked in processed for the busiest one of the 3, it had a ticket that had processed (wasn't me or my intervention) and checked in the client and it had logged the ticket via the monitor. This brings me back to the original subject "Email monitors - Mind of their own?"
I guess what's really happened is that the service was stopped by support but it's take a little while for this to stop impacting the prod environment.