Originally Posted by
Duke787
DL requires the use of RUCs, miles + cash, or cash to upgrade but I believe only you can only use RUCs if you are a Diamond (a Platinum with RUCs can't use his/her RUCs on this route).
This is actually not accurate, based on my recent experience. I definitely used an RUC 2 weeks ago as a Platinum to upgrade to the front on an overnight nonstop flight from LAX to JFK. My upgrade didn't clear until 30 minutes before departure (10 minutes after boarding began), so it was pretty stressful waiting to see if I got it, but i got it.
Also, I am about 99% certain that the only flights on this route that are Medallion Upgrade restricted are the nonstops with the "Delta One" front cabins - the ones with the lay-flat seats. Flights with a connection are eligible for upgrades.