Asian L/H
I believe it was some arcane element of Korean labour law, not specifically something dreamed up by KMOCT or the airlines.
This is the way it was a couple years ago. Someone has suggested to my that some contractors are saying this situation has changed. All I can say is: if so, ask for proof in the form of someone who has jumped from Brown to Blue or vice versa. Otherwise it's just a theory.
ELAC
PS ... Anyone who knows anything about Korea has to be a bit sad today over the fire that has destroyed Namdaemun, the historic south gate to Seoul. It has been there for more than 600 years and was considered national treasure #1 in Korea. I walked by it and looked at it many times during my time at the Seoul Plaza and it was indeed very beautiful piece of Korea's history. My heart goes out to my Korean friends over the loss.