Those of you that can't wait for World of Warcraft: Legion, you can get even more of a taste (besides the 7.0.3 pre-expansion patch) on the 9th of August, 2016. Blizzard is making the new Demon Hunter class available for those that have World of Warcraft: Legion pre-ordered, as well as the ability to experience Demon Invasions (which drops sometime around the 9th, but no further from the 17th of August), where Demons will invade popular cities of Azeroth.
World of Warcraft: Legion is set to release on the 30th of August, 2016.