#1 - Sept. 19, 2014, 7:59 a.m.
Blizzard Post
Please see source post at http://eu.battle.net/wow/en/blog/15910701/get-warlords-of-draenor%E2%84%A2-now-upgrade-to-the-collector%E2%80%99s-edition-later-18-09-2014 for detail.