Friend at work is in the same position you're in, they wanted to charge him the rest of the contract.
He keeps complaining, he's getting higher (slowly) and with each new manager he talks to, the amount's going down.
His reason is that he was promised full signal at home, he gets none. So it may be because he's got a good reason, they will concede.
So yeah, they'll try to charge you, but keep on (he's been doing it for over a month now) and they'll drop the price
hope that helps
Tom