1. 11.1 Subject to clause 11.4 below we may increase or decrease our Charges at any time (including the introduction of charges for aspects of the Service previously provided free). Where we increase the Charges for the elements of the Service you are using we will notify you before the changes become effective. Notification will be via text message or by email (if you have registered your email address with us).
2. 11.2 We reserve the right to change our terms and conditions of Service from time to time. We will notify you of any changes to these terms by posting them on our website at www.o2.co.uk/terms
. In addition to this we may also notify you by messages on our IVR top-up system, messages via the Service (such as voicemail, text or media message) by means of national advertising campaigns or by email.
3. 11.3 If we vary any of the Charges or change the terms and conditions to your disadvantage, you may stop using the Service.
4. 11.4 We will not notify you of call charges for premium rate services operated by third parties. Details of these charges and any changes will be available on our website (http://www.o2.co.uk/premiumnumberpricing
). Please check these before calling premium rate numbers.