There's not. Delta bugs out bad with KE. Even for paid tickets. It shows inventory that's not there and then if you call, they'll say the website has a bug and it's actually thousands more or totally gone. AND Korean Air only releases literally like 3 biz Class seats for their own members and they get snatched up the day they go on sale a year in advance. You're not gonna get anything this close to time booking through Delta. Even then, Delta, I believe only gets ONE seat per flight and that is gone the day it is released.