I made the mistake of falling for the cheap contract in the Sun and b4 I knew where I was I'd agreed and paid my £129 line rental in advance. Turned out when email after email started arriving it did NOT offer the same as EE (my previous provider for eleven years; Freeserve/Wanadoo/etc continuation loop)
I wanted all my local UK calls free as I had don ewith EE. It required more money for me to get that with BT. I cancelled by phone with three weeks remaining of my month. I called one more time just to be certain and yes BT confirmed " yes all done for you; you won't be switching to BT and you'll get a refund."
I phoned again a week later; same M.O; no probs I felt safe in the knowledge that BT had cancelled me. I emailed to make certain I had a record. Reply stated same; duly cancelled.
I was amazed when on the 27th Feb BT took over my line and my BB!!!!! It then took over a week to get someone to call. Long story short, I'm stuck on a new plan now which effectively gives me inclusive calls. The generic email does not though show what the email said. It does not reflect my £129 in advance. My email then to ask why it said what it said, was replied to me not to worry, it won't be £29.95 a month; it will be as I agreed!"