Just a note to say that, to my surprise, Supanet have provided me with a MAC Code free of charge. Now I am not sure whether this is standard policy or whether my moaning finally got something done, but on the evening that my Supanet service was due to terminate (cancelled 28 days ago and was expecting to have to wait 4-6 weeks for new company to set up) Supanet provided me with a MAC Code. I was rang out of the blue and told that "it was my lucky day" and that I would be provided a MAC Code free of charge. Once I got over the shock, I took down the MAC Code and I was also offered an additional months service at a reduced rate, in order that I will not lose coverage whilst transferring services. Cancellation date is now 27 March and I should be able to transfer with minimal distruption (touch wood).
Just thought that as I have previously voiced my annoyance at Supanet's behaviour, I should also let people know when they also act in a reasonable way