Well I phoned Apple support and they sent me to the store at Meadowhell, they didn't have any idea about the problem but replaced my iphone 64gig 4S with a new one. When I got home and tried it the problem with the location services was still there, i.e. it locates me about 50 miles away in Manchester.

It is definitely a 4S problem as the other iPhones in the house don't have this problem, also the location services work correctly if I put the phone in flight mode, turn WiFi on and turn the location services off and then on again so the phone is just using WiFi triangulaton, so it must something to do witht the way the 4S uses the phone masts to determine location.

I am now currently doing some testing in conjunction with Apple's second line support, I will keep you informed.

Top tip, if you are going to an Apple store make an appointment first as people that hadn't were queuing out of the door when I went.