failure I'm afraid. The attached picture of the Register page shows that a Certificate for this Registration wasn't issued, and as can be seen the previous No. suffered the same fate - in view of the fact that both Registrations were dated 27th August 1936, this might just lead to speculation that both Nos. were originally granted to the same Registrant, but that's only an opinion. As can be seen, both Nos. were originally declared as CLASS IV, the most common reason for omission from the Blue Book.
Unfortunately, the Representations book is without any image of 814921, so in view of this lack of information it's unlikely we shall ever know details of the Registrant etc.
Just for the record, Kew references are …………… for the Representations book (the images) it's BT 52/2052 - for the Register (details of the Registrant) it's BT 53/72