I just bought an iPhone last Wednesday from an Apple Retail Store and activated it on Friday 1st February... can i return the 8GB iPhone and pay the difference for the 16GB model instead?
How about the contract with O2? will the my 18-month contract be extended another 18 months (36 months / 3 years!) ?
Under Apple and O2 policy you should be able to return your phone within fourteen days for a full refund. At worst your contract should remain the same and you will be able to purchase the 16giger while refunding your 8giger. Otherwise claim it as faulty for a full refund...