Really odd. The app also told me my flights were cancelled and I would need to choose new flights. I bit the bullet and chose the same ones again, and now my booking seems to work normally. Just seems an odd way to manage such a situation if I was already rebooked onto these flights anyway. Good news is one my my sectors went from old A330 to A350 with the new Business Class. Looking forward to it (and hoping for now adverse rescheduling)!