Jon Collins, from Hull, says he has temporarily stopped making chocolates due to high temperatures.
Cambridgeshire Police says the vehicle is being further examined and its inquiries are ongoing.
The Cadbury bar from the Second Boer War was commissioned by Queen Victoria.
Mars bosses say the investment means it can now produce five million chocolate bars in Slough a day.
A court in Bremen has found the manufacturer of the classic Alpine Milk chocolate bar guilty of "shrinkflation".
The Birmingham-based chocolate maker said the limited edition bars would go on sale later this year.
The 126-year-old chocolate bar is described by auctioneers as "very rare, if unappetising".
The author, who visited York Chocolate Festival, says she has synaesthesia and can smell colour.
Billy D'Souza spent more than £600 on 22 Easter eggs to highlight the rising cost of chocolate.
