Just today--yes a Saturday morning flight--MSP-PDX, on which EUA did not run (showing P4 six days out) I got to the gate and was told that there were STILL 4 seats available, and I was 4th on the waitlist--how perfect!
About 35 minutes before the flight was to depart, someone walks up and asks how much it will cost to upgrade. I didn't hear the amount, but she looked at her significant other for approval, and shelled out a bunch of bills. As soon as I saw that I scurried to Famiglia Pizza in Northstar Crossing and got their "special" (thin crust with loads of toppings, including lots of onion). I managed to get back to the gate and scarf down the pizza before the upgrade list was called. ONE elite only got called up for an upgrade.
5F isn't all that bad a seat, even on a 3.5 hour flight.
But plats in back on a Saturday morning?!?