Just signed up here after google searching about BT upgrading, and found this site. I Saw this guys problem so am giving a possible reason:Originally Posted by Marcos
From BT-
So that may be why you have sucky speeds...6. What happens if I exceed my monthly usage allowance?
In the unlikely event that you exceed your monthly usage allowance (remember these are more than enough for the vast majority of users) the speed of your connection will be reduced to 150kb until the start of the next month, when you monthly usage allowance will be reset.