To change or not to change... that is the question

[#1]

I am currently on Premier Option 1 and have been since I joind PlusNet in 2005, and this package with unrestricted bandwith from midnight to 4pm suits me well. My line rental and call package are with BT, Unlimited Anytime.
With the announcement that 0845 and 0870 numbers are going to become part of Plusnet's call packages I am tempted to change my calls to Plusnet from BT, and as a combined package is cheaper, change my broadband to Unlimited. Overall this should save me around £7.00 a month (if my maths and understanding of the charges is correct!)
However I have also read that my exchange (01248) is due for upgrading to 24Mb between Oct 09 and March 10.
Now for my question - if I change my broadband now I will be tied into a 12 month contract (I do not need the router), so does that mean I can't upgrade to 20Mb when it becomes available?

[#2]

Hi there,
If you move to unlimited now, you'll be able to take an annual contract.  However, this will essentially become a monthly contract once October 22nd has passed, assuming you have no deferred contracts (which you won't).