Mr. Barry Lowry:

Mr. McCallion may wish to add to this, but our process is to investigate each instance of an undelivered certificate. In the case of many of the posted certificates, for example, we have been told that the addressee has simply gone away, and that might mean the person has left the country altogether or that he or she is now living at a different address. If we do not have the new address for such a person, or his or her email, then it will be a case where we really need that person to contact the service desk and provide us with information to allow us to resend the certificate.