When I recently received cable broadband, it was made clear that I could pull out of the contract right up until the engineer delivered the box. Once I had accepted delivery of the box our contract would be binding whether or not a paper signature had been received by Virgin Media from me. This was in black and white on the contract I was sent ahead of time.
So, it would be the case that you are in the same position. Now you have accepted delivery of the 'box' (or mobile phone in this case) the contract is binding. Virgin Media can no longer back out. They can stop taking your money if they like, but must provide a service till the end of the contract period (just as I could now cancel my cable broadband service, but would have to pay until the end of the contract period). Surely this must be the case? Put it to them and see what position they take.
Can you tell I'm a union rep?
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