Talk Talk have just changed my broadband without my permission and without a Migration Access Code. In fact, my wife specifically told them we already had a broadband provider and we weren't interested in changing immediately and was told they couldn't migrate our broadband until they had an access code anyway, so the ball was in our court.
I noticed that my broadband modem wasn't managing to log in after coming back from a week's holiday in Italy. I'd been sent login details (which I assumed were for my online account but which I knew would work as an ADSL login/password beacause I'd set up my mother-in-law's), so I changed the login details in the modem, and hey presto! I had broadband again.
My former ISP (Force9, owned by PlusNet) were very helpful and didn't complain or try to offer me a special deal that would end up costing me more money (which is what Bulldog tried to do in the past) and have behaved like a paragon of service providers.
If it wasn't for the fact that I'm saving £22 per month, I'd have stayed with Force9. And if Talk Talk provide me with a rubbish service, I might just go back to them.