Originally Posted by
percysmith
Interesting theory but doesn't match the facts - Y was booked out/(withdrawn from sale) first - as of 24 Apr I saw J2 Y0
That makes sense to me. Y goes 0 first, then slowly eats into J.
My guess is that they had enough overbookings to swap in a 77Z, which has a lot more seats than the 74K. The said 74K then took over the other route which probably wasn't fully booked.