You're right - I eventually resubmitted a new code they gave me, under the impression that this would give me an hd copy, and lo and behold it was SD again. Only after the fourth email did they, still slightly cryptically, that this was a feature they may adopt in the future. I found that both apple and fox avoided my explicit and direct enquiry about SD vs HD downloads on this specific Bluray, and only eventually addressed my question after several back and forth emails.
Yet some people, a couple of pages back, claim to have downloaded an HD copy from the same product edition as myself.