Stable update site (1) seems to be not updated to 10.3. They contain text "Latest Build: 10.2.0.GA" and links to Update site zip, Target platform zip, etc. are pointing to 10.2.
Problem is probably only in html page, because when I try to install BYOE from (1) then I see that update site contains 10.3.
The central and early access folders for 10.3.0.GA are missing in  and .