I always wonder about that kind of disparity. Maybe a young child on w/adult and PO was for coach. Or they never showed at the gate? I see same S2s are listed for today. Then again maybe GA screwed up the seating? I thought only CDG screwed pax out of rightful priority! (they did that to me twice not long ago).
My nephew is very flexible on S4. I watch and tell him to MOVE IT!! when necessary. Once, I called him in FLA and told him to get his butt to DAB now, since next few days looked poor unless he wanted to fly coach...