And of course DL doesn't use KE's blackout dates on a route-by-route basis. If ANY route is blacked out on KE, you can't use SkyMiles to book ANY KE flight during that period, whether they include that route or not. For example, if KE has just Korea-China blacked out on the 3rd-4th of March, you can't fly on KE AT ALL on the 3rd of 4th of March using SkyMiles.