The Yeo Society web site
This site states ” The first mention of the surname Yeo was one William atte Yeo , who was Sheriff of Devon in 1359″ (Wikipedia states 1358).
However, there are records stating that Richard de la Ya (known as Yeo) married Joan Bauzan – and their son William Yeo was born in 1255 (this is a different William Yeo to the Sheriff of Devon).