Congrats, Carol and ms_go!

I think that your chances are excellent at getting the upgrade on return. Because of your M/H fare you just jumped over any 1Ks that that booked at lower fares using SWUs (if those fares were ever offered).

I would call United, though, because of what happened in the past. I believe it doesn't happen anymore. What it is is that the status you have at the time you book the ticket stays with the ticket. You used to have to call and have them make a change to your PNR.

Maybe ms_go knows if that call is still necessary. I'm willing to call UA and find out for you.

After I made that last post I remembered that I had to cancel an award ticket (alas, I won't be going to the World Series), so I asked about your situation.

I confirmed with the agent that the PNR for your return does in fact show your 1K status.