leigh,
i was wondering about the extra holes. i had not noticed that the crown on the badge and the crowns on the chinstrap buttons were different. we will have to look into finding the proper badge to see if the holes match up. it is a very high quality officer's cap, with a tag identifying lord nuffield as well as nuffield hand-written into the top of the cap. we also checked with the keeper of nuffield place, who believes this cap came from the uniform they have in their custody which is missing its cap.