I've received my SM status. I had a trip booked before this status update and I'd like to request an upgrade. The ticket is a U class. How do I request an upgrade? Do I call one day before departure?

Thanks!

Log into your account, pull up the itinerary, and look for something like "request upgrade" to click. If this does not work, call DL at your new Silver number or not, enter your DL FF number, and ask to be added to the upgrade list. It is best to do this as early as possible so that you can check on the computer that it was done right. If this does not seem to work, try removing and re-entering your FF number, or ask a phone agent to do this, but this is not supposed to be necessary any more.

If the flight is very empty in FC, Silver upgrades should clear at about 5-6 pm in ATL TWO days before the flight or you might get a gate upgrade.

One more piece I should have asked in the original post. What are the chances of me being upgraded and my girlfriend (not SM) not being upgraded? Would I have the chance to decline the upgrade?

This would depend on the flight pairing (to/from) and day of week/time of day. But as a silver, chances are usually pretty slim all around.

Yes you can decline an upgrade. Just tell the GA. Better yet, tell the GA in advance that you don't want the upgrade unless GF gets upgraded too.

Hard to give odds without knowing details of route, day, and time.

One argument is that if Silver gets UG, FC must be wide open so GF will probably get UG too. OTOH, if Silver gets UG, one can argue that it's likely to be the last FC seat. So, it depends.....

I had a ticket I booked before I became SM, and it instantly changed to 'upgrade requested' for all outstanding trips, so it might just do it automatically

Companions of "silvers" are upgraded last, correct? That is, after Diamond, Platinum, and Gold traveling companions have been upgraded?

To the OP -- it really depends. I was actually 2 for 2 getting companions upgraded as a silver, but those were (obviously) very elite-lite flights. Saturday flights are probably your best bet in my experience.

Yes, of course DM, PM, etc. companions are upgraded before FO companions.

Mine say "Upgrade Eligible" and I'm now about 6 hours into my upgrade window... there are still plenty of F seats available, should I be worried?

Don't they need to say Upgrade Requested? I needed to call in to change that status on my upcoming flight.

Yes the flight segments must show 'Upgrade Requested' for you to be on the upgrade list. If it just says upgrade eligible, then the system doesn't have you in there to get upgraded.

Direct message @DeltaAssist via twitter with the confirmation code and they will take care of it for you in 2 minutes.

I am shocked that this is the only non-phone based method to put in this type of request reflected on the Delta website. I'm on hold... and not impressed.

It's possible U fares aren't eligible for companion upgrades.

This is the problem with Delta IT. It is very fragmented. This has been a problem for quite some time. Also a problem if for example Kayak or some other search engine sends you to Delta to book the ticket. Even if you are logged in it will not request the upgrade properly and there is no way for you to manually fix it. And yet the @DeltaAssist folks are really quite incredible and fix even the most complicated problems within a few minutes with a single tweet.

So much better than calling a phone number, punching in a bunch of numbers, sitting on hold, and then often they can't seem to figure out the problem. They'll tell you something like "They haven't yet released the upgrades yet" and you'll tell them "but it is not requested" and they'll say "you are silver so they haven't yet released the upgrades yet" and you'll say but can you please just request the upgrade and they'll say "You are a Silver and they haven't yet released the upgrades". After you throw your phone across the room and go pick it up, you'll tweet @DeltaAssist and they'll fix it in a second and apologize and tell you how much they appreciate your business. I'm not kidding.