This is not a scam or anything and I have used it to get out a 18month contract, without any fees,
basically orange have increased their charges, instead of advising customers exactly what the new prices are and options available to them, they simply sent text messages to some customers, every so often, saying that your plan has changed and for more details please visit their site or call and speak to an advisor.
If your like me, hate receiving the spam messages, then most likely will have deleted as soon as you read the words 'from orange'.
No worries all the details are here and explains how to cancell it too, its not a scam and your not breaking any laws. Because they have increased not one but almost all charges, such as calls to uk landline, uk mobile, uk orange to orange etc, it states in there terms that you can choose to cancell.
BTW took me 2-5mins to get it cancelled and it was effective the very next day at 9am!
Bumped in to this whilst browsing OC.co.uk forums, after buying new cpu cooler.
Cancel your Orange contract now! - Overclockers UK Forums
and their source
Orange Price changes ? - MoneySavingExpert.com Forums