Before this October we had always got the seats I reserved.The previous 3 times as we reserved through special needs dept as my son has Aspergers/autism.
When we arrived 3 and a half hours before check in this Feb and we were travelling PE so apparantly don't need to get there until 2 hours before check-in we were told you haven't pre-booked seats and that we were the last to check in and were to be seated seperately

I had booked the seats at the 180 window and even callede VA the day before to check I still 'had' my seat allocation.
Bearing in mind this was our first holiday alone in 20 years and that we live an extremely stressful life with a teenager with behavioral/anger problems and that we had dropped my DS off at Grandparents house and he had hysterivally chased us down the road in the middle of the road as we drove off for such a long way leaving DH and me very upset.
Then to be told we were to sit seperately,I was about to burst into tears when the check in person said I'll see what I can do.As she went off my upset was very quickly turning into anger.Anyways she gave us exit seats so all was OK.
When we got on the 'plane I was looking at the family in 'my' seats and wondering why they had been re-allocated on this occasion but honoured always before,I don't know.
I'm sure all the people who use twilight check-in mean it is more unlikely for people like me who can't stay overnight at the airport to get what they had booked!