Originally Posted by
colerc
Looking at some European flights for next week and the seat maps suggest there is some chance of op-ups (half full J + nearly full basic Y seats + nearly empty preferred/EC seats)....
That looks like pretty slim chance for op-up. You need completely full Y cabin, including preferred/EC seats. Furthermore, seatmaps are nearly useless for predicting op-up. You need to look at fare buckets.