What does the router say your connected at, and what does the BT Speedtest say your IP profile is?
Where did you get BT telling you they want >£100? Your contact is with Pipex: there's no one at BT that you can speak to who can help.
Where did you get BT telling you they want >£100? Your contact is with Pipex: there's no one at BT that you can speak to who can help.