Nope the speed upgrade is free so you continue to pay the same monthly price as you do now. If you ring the number that "Marge" gave you on the options thread you need to press the option for package changes etc and that should put you through to the people that can help with your account. Think it's option 2 but the thread the info is in is now 3500+ posts long
Oh and while you are on the line to them you could always ask if your upgrade can be put through while you wait. They might do it there and then if your area is ready for the upgrades.
Oh oh, now someone is saying option 5, since that's the option we used here then it's probably the one you want too