"DO make sure you request a waitlist of the class of service you've paid for-- your stand-by priority for that (if you don't clear in advance) will be ahead of all upgrades. You paid for the better seat, after all."

IK-SFO, although this would be true with SFOPremex, UA's system is very sloppy and it's very likely that because of THAT, he would NOT be ahead of upgrades for the return unless he baby-sits that waitlist and then gets to the airport several hours ahead of time to be sure he's put at the head of the DM list when UA drops the ball if he doesn't clear before flight day..

I had the same experience, where I was assured by UA reservations that I would be ahead of all 1Ks who wanted an upgrade at the airport when they did the DM list..at the airport, the gate agent gave me a dumb look & said "gee, you're not ON the list." I had paid with miles to upgrade both myself & my wife. It turned out that only 1 FC seat remained so I let him give it to one of the long list of those wanting to upgrade..

My feeling is that the waitlist does NOT carry over to the airport control DM list (or they screwed up big-time in my case). Unless you get to the airport hours early, you'll only get a spot on the DM list from your check-in time. And unless you make a stink about it, they won't give a rats ... that you already paid for the upgrade..