Olibabba, I need a bit more info. What airline are you flying? DL folks using leisure ezeds are not entitled to upgrades unless our travelnet agreement says so. I am aware of one AF emp moved up the list by DL but they may have been due to buddies? However, they were only upgraded to Comfort+ in coach.
Use your travelnet to get the terms. We recently flew Air Malta (KM) and bought rev tkts one way, but after a brief call to their tkt office, the good news was "plenty of seats" with yellow straight faces on ezed, we chose to go that way--about half price. Yep--lots of seats! We even got assigned seats before heading thru passport control. Do you have skype? Great source for contacting OAL offices. They are usually quite nice--use the term "staff travel" for overseas.