I did not see a definitive upgrade thread, so posting here. Mod, please merge if I missed it.

1. My SO and I are going to las. I figure its usually a common flight to be full and elite-heavy (totally speculating). But we are flying Sat - Mon. I am PLT and she is GLD. What are our chances of an upgrade?

2. Sitting together is def. more important than first class, so I should 'marry' the two PNRs together, right? (We booked it separately). I am guessing that kills the chances of an upgrade. But I cant afford mine clearing and hers not, and exchanging my seat with someone else and wasting my stickers.

3. Is there something I can do to have any chance of an upgrade? Sure, the T-4, but should I just tell the PLT desk agent anything else besides to marry the PNRs together and click upgrade online on both accounts?