I don't see in that article that they are planning to unfold them in flight. There is mention that "In parallel, Airbus UpNext is accelerating the eXtra Performance WING demonstrator, focused on developing a wing that can change shape during flight" but that sounds like a separate project.

My guess is that they will be folded after landing, and unfolded prior to takeoff, as other planes with foldable wings do, so that they can continue to fit in standard spaces in the parking/gate areas.