I had a couple of wobbles on my iPhone 5s in the last week on both occasions I lost network services, and on both occasions I was being told I was waiting for an update from my carrier although the phone itself is telling me that the phone was up-to-date. This first occurred after an iOS upgrade, Then again after I attempted to restore the phone from the backup. Apple talked to me through it on both occasions. On the second occasion I went back to factory settings and then reloaded. During the factory reset the box appeared asking if I wanted to download the software update from the carrier I.E.02. Obviously I said yes and all was good. I wonder if any other users have encountered this issue and whether there is something missing, That he is preventing the carrier software from upgrading when O2 updating the operating system, And whether it is possible to force upgrading of the carrier software if the phone is adamant that the software is up-to-date
