Slipping through the net
The 1939 Register had some notable omissions
In trying to register about 40 million people within a few days, inevitably some were missed out, and had to report to their local National Registration Office to register in person. People who deliberately avoided the enumerator, possibly because they thought that they could avoid being conscripted, were in a minority. But in most cases failure to register was due to misunderstanding, or force of circumstances. When they realised that no identity card meant no ration book, people were keen to sign up, but only those who were registered on 29 September 1939 will be found in the online register.