There is reference to Hill 880 and an attack on this link (which is an abstract of an e-newsletter), search for Hill 880 on the link:
http://www.dehs.org.uk/wp-content/up...-I_Extract.pdf
It would appear there was an article originally in a magazine or publication called "Radar" put out by the USAAF in the 1940s.
Mike Dean then most likely contributed that original article, which was then published/re-published in the July 2017 e-newsletter.
You may have to be a member of the organization to actually see the newsletters, I don't see them on their website, only the abstracts.