OK, here is my situation. I have a PS itinerary from SLC-MSP-ICN-HKT. Delta operated from SLC to ICN (used GUC to D1), Korean segment from ICN-HKT is in economy and Delta says there is no way to upgrade that segment to Prestige unless I buy a D1 ticket outright. I have read that having the KE economy in J,C,I,D,Z fare class makes it upgradeable however, Delta says they cannot book into a specific fare class. DM line agents have told me different information 3 times. I have told them I am willing to cancel the whole ticket and start from scratch buying an upgradeable PS ticket, but they say they cannot pick which economy fare class on KA. Anyone have any experience with this? TIA.