Mate, if you are adamant your documents don't specify the changes, then you should not have to pay for it. If you really want to stand your ground on this one, ask to speak to a manager and if that doesn't resolve it, ask them for the address to make a written complaint to their Customer Relations team. If your issue is still not resolved then, you can write to the FSA, although i doubt it will get that far. Chances are, as soon as you complain to a manager, they will write-off your £10 charge. Hope this helps mate.