We have it on high authority that there will be a £25.00 one off payment.
The benefit to the customer is that they will be on a bigger download bandwidth for the same money per month.
The recent "automatic" upgrades and the proposed "£2 5" upgrades have both meant substantial changes to the Infrastructure to accomodate the new speeds. These changes cost money, and ntl have paid for this already.
Why would they offer increased speed for free ??? It's a business for christs sake. They are there to provide a service and expect to be paid for it.
£25 one off fee .... then continue paying what you were before, for a faster service, hmmm, difficult choice

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The choice is yours. If you don't like it, don't do it or leave. simple really.
The upload speeds may be changing too, we are waiting confirmation.