I eventually got there. They were failing to get anything! Live Chat was a complete waste of time they were annoyed that I wouldn't tell them why I wanted to leave, or listen to their retention speech. The Live Chat was closed by the operator.
I emailed complaints included my full name and account number in the email. They replied that the details I supplied didn't match their records, and could I let them have my full name and account number

I replied and included the details requested.
Received another email today from Customer Services asking me to ring them regarding my "account cancellation request". Spoke to a Scottish guy who gave me the MAC over the phone.
Three days to get a MAC is laughable. The Scottish guy basically said the overseas call centre was a waste of time.
Plusnet FTTC ordered this evening.