Change in Airbus assembly schedule. But the aircraft has changed registration to JA07WJ, and that would not happen if there is still assembly to do from Airbus' side. I'd still lean to seat being missing, or not being up to the usual rather shoddy standards from Safran. But I guess we might never know, unless we happen to get a seat next to Tottori san on a flight, and she is talkative.