I wonder what OFCOM's take will be on this [:?] As technically, as long as you have fulfilled your contract obligations, you are entitled to get your handset un-locked from your network.
Quote from the OFCOM web site:
Mobile Phones - Advice on switching your mobile phone supplier
Most mobile service providers require a minimum service period or contract term before you can switch to another provider. If you purchased your mobile phone with the service from your current provider, you have the option of keeping your current mobile phone, however you must make sure that you do that within the contractual terms of your existing mobile phone and service.
Whether you are a post-paid (contract) or pre-paid user, you can keep your current mobile phone by requesting that the SIM lock on your mobile to be removed. Usually, mobile service providers require a minimum contract or service period to expire before they unlock your phone. Most service providers charge a fee for this service
OK so this wont apply until you are past your initial 18 month contract period with O2 but what then [:?]
Most networks also dont actually charge you for unlocking handsets, as long as you have fulfilled your contract terms. Well at least V Mobile dont.
Regards