You are obsessed posting everything you see relating Spaniards and North Africans...what a sick agenda.
First of all, it is impossible to measure the age of the componenets in a population. However, the presence of North African admixture in places wich were never conquered by the Moors, suggest that the vast majority must be ancient. More or less is what the text is saying...a range between 800 and 1700 years it's not exact in any case. There are so many open possibilities, and in places never conquered the answer it's very easy to infer.