Could it be the preview they mentioned for next week?
Super Hype About RtH, but Where is Our Next Wave 4 Preview?
I really think the preview for next week is going to focus on the Rebels for Return to Hoth and potentially touch on the campaign or multiplayer skirmish structure.
Not sure there's a whole lot more to say about wave 4. They gave a decent amount of info in the announcement article.
I just want to see wave 4 go from at the printer to on the ship.