Programs: DL FO; TK *G; HHonors Gold; SPG Gold; Points but dirt with everyone else
The only way to use SkyMiles to upgrade KE flights is through the SkyTeam upgrade program. This requires the purchase of a Y fare, perhaps even "full Y", as in the most expensive of all the published Y fares.
Follow up from my experience. This takes a few days for the ticket to re-issue so be sure to do it as far in advance as possible:
1.) Look for your flight that you want to book on KE and price it out on their website. Write down the fare basis code.
**Be sure to check that your dates of travel don't fall in KE's blackout dates**
2.) Call Delta and ask for the SkyTeam upgrade desk --the res agent I worked with made it sound like it was another desk like say the "International Re-ticketing Desk"
3.) The Delta ST Upgrade Desk will provide you with six or eight fare basis codes... make sure the fare basis code that you got from KE matches one of those they gave you.
4.) Book your ticket on KE. (Again make sure your dates aren't in KE's blackout dates)
5.) Call back the Delta ST Upgrade desk and ask to upgrade your ticket. If they run some stuff passed you that only KE can "endorse" the ticket (i.e. release it) , that isn't true. Delta actually has to call or work with KE to get KE to un-endorse the ticket so Delta can upgrade it. The first agent I spoke with on the ST Upgrade Desk couldn't do it but the second one did it in about 5 minutes. It sounds like Delta has to take your flight information down and pass it to KE in order to upgrade it.
6.) A few days later, you'll get an email from Delta in a standard reservations format email but with your KE flight and upgrades confirmed into Z. My upgrades cost 30k miles from DXB to ICN and 40k miles from ICN to SYD. I didn't see a cost chart anywhere though.