Segrave's 203 MPH Sunbeam

This photograph was provided by the curator of the Paul Sheedy Collection. Taken in Wolverhampton, England in 1927, the car was the Sunbeam 1,000 HP Mystery, nicknamed, "The Slug." Driven by Sir Henry Segrave, the car became the first to eclipse the 200 mph barrier on March 29, 1927 on the sands of Daytona Beach. This established a new land speed record of 203.79 mph. I cannot explain the margin note stating that the speed was 207 mph. There may be some explanation, but I believe it is simply a mistake.