Well, maybe because now update "flagships", though "old" and "Alpha" has never positioned itself as a "flagship". It was probably the first experiment ... "pen test", if you will, at the expense of the metal housing, etc. And by the way, the "A" series (A-3) was the first in Russia to receive the upgrade to 5.0.2.
This is my personal mnenie..A about "the release date of the update" or who does not know anything and can not know.