At E3 2014, Respawn announced their upcoming June title update for Titanfall. The new update features new game modes, titan customization, voice overs, and more. You can read more about that here.
Respawn has also confirmed that they are adding achievements for the Expedition DLC pack. The Expedition DLC launched in May on Xbox One and PC.
You’ll see our E3 content in our next update (and achievements for DLC 1!)
— Respawn (@Respawn) June 10, 2014