2006 (04) Queen's 80th Birthday - Bletchley Park Official - DOUBLED with a Windsor Castle CDS

Cracking Bletchley Park Official but DOUBLED with a Windsor Castle CDS.......

From John Chapman's personal stock - no idea how he did it, but he managed to get a few of his standard Official's get an extra Windsor Castle CDS cancel (with the correct date) on the middle four stamps - PLUS another Windsor Castle CDS strike on the rear......

Suffice to say - This is pretty scarce !

Code: 51045