Not for me. Sitting in the back a lot. I typically book a few weeks out and can pretty reliably predict whether the CPU will clear based on the current load in the F cabin and my fare class.

While this is probably the subject of a different thread, there's clearly something afoot on some of these flights where I'm way down the list. This week, DEN-FLL flight. Flight was mid-day and mid-week to a tourist destination in the height of spring break season. This was not a typical Thursday or Friday night hub-to-hub flight. I finished #7 on the upgrade list on a pmUA 757 (24 seats in F). According to the mobile app, about half the folks in F were "upgraded" by some means or another. The other half apparently "booked" some variant of F or don't show on the mobile app as upgraded.

There's no way to convince me that:

• A dozen people paid a full F fare to sit up front on a four hour flight.
• There were really 17 or 18 people ahead of me on the CPU list--it's highly unlikely that there were that many Y or B fares, or GSes, or even 1Ks on higher fare classes.

So I'm forced to conclude either they are (a) extremely successful at selling F seats at reduced rates, either through V-UP type fares or ToDs, either at booking or at check-in, and/or (b) the CPU algorithm isn't really as advertised. I'm slowly becoming convinced that (b) is a possibility as well somehow.