I had preselected 45E and 45F for my wife, baby daughter and I due to the bulkhead position but with a movable armrest (easier for baby daughter to sleep on me without kicking the armrest). Checked in online and received mobile boarding card with 45E and 45F.

Came to airport, checked in luggage, received boarding cards, saw 45 and didn’t check the letters. Get on board, a sweet old man and his granddaughter came and said he and his granddaughter had 45D and 45E and sure as hell, turns out we had 45F and 45G instead...

I know airlines can change your seat without notice but since we had preselected, had a baby, etc etc, a notice would have been nice. I am also curious what would have happened had I not had any luggage checked in and just went straight to the plane.

I wasn’t going to complain to the purser (because I assumed he would just try to ask the old man and his granddaughter to separate and I didn’t want that).

Hasn’t ever happened to me before on any airline. Has this happened to anyone else (excluding op-ups - in which case you get notified anyway)?