You have to wonder at the ease with which boys were accepted into the armed forces in WW's I and II by simply lying about their age. Even in those days there was an abundance of records other than the paper Birth Certificates, which obviously were not presented when required. By simply demanding details of place and date of birth the local Registrar could have confirmed or denied the claim. Admittedly it would have to be done via the Royal Mail, but it wasn't snail mail in those days and delivery was often the following day (sometimes sooner!). Could it be that HMG was content to make up the numbers in this way? If it were not so, the RAF had plenty of time to discover that Cobley was under age long before he got airborne for the first time, let alone go on Ops. With all the RAF record keeping involved, re training, jabs, postings, promotions, etc, etc, all of which would be authorised and confirmed, how come the most basic detail of all, ie dob, was simply taken on trust?
If his father had not seen the picture of his son and the King in the press, would it have ever come to light? If he'd remained serving continuously he could have smashed all records, making Gibson appear an old man as a Wg Cdr....