This has all but been confirmed by Blizzard but an article has been released accidently early claiming all.
There will be updates to Battlegrounds and Duels. The original article also claimed the release date of Anduin Book of Heroes chapter, though they deleted the original post.
Also, importantly, there was a statement about a mini set bundle for $15 / 2000 gold that will give all cards right away.
This is all rumor and is based on a now deleted article but it is the best lead we have till Blizzard makes an announcement.
Happy Ranking Y'all!
blad probably gonna be like more like $35 knowing blizzard. big up myself and the horde side massive.