OK, guys, explain this one.

I'm a 1K travelling with some family members who are silver elite tomorrow through IAH on a cheapo fare.

The flights looked pretty busy. and I haven't had a lot of luck on Thursday upgrades, so I just split myself off into a separate reservation. I didn't try to do any companion upgrade.

I've checked myself in, and I'm currently 20th on the CPU upgrade list to IAH as shown on mobile.united.com. On my connecting flight, I'm only 12th.

That, of course, is better than my silver elite compatriots. They're in the low 50s on the first flight, and in the high 20s on the second.

Now I'm not terribly surprised I didn't get an upgrade -- as I said, the flights look crowded, and Thursdays aren't great for upgrades into IAH. But that said, how is it possible that I'm 20th on a 737? According to the published rules, there would have to be 19 GS and 1K pax on higher fare tickets in front of me. Right? I don't think that's statistically possible. Are there certain published fares that trump my elite status on the CPU list? There has to be. Right?