Clearly a first world problem, but........

On ~9 of my last 10 successful CPUs, I've been automatically assigned bulkhead aisle seats by United's computer system, despite the fact that I have always had "Window seat" selected in my travel preferences and despite the fact there are window seats available. Does anyone else consistently have issues with this? i.e. system over-riding/ignoring seat preference

Case in point: I have a flight tomorrow morning on an A319. Upgrade list showed 3 of 8 booked, and upon check-in I was offered a cash upgrade (declined) which confirmed there were 5 F seats available and 5 customers eligible for an upgrade (like those odds!). Seats 1BEF and 2AB were available - I was number 1 on the upgrade list (of 4 checked in at the time), yet when the CPU process cleared 4 of us into F (at t-23hrs), I was put into 1B. Only seat left open was 2B

So, I'm wondering whether the CPU seating algorithm just fills the seating map left to right, front to back and completely ignores your pre-set preferences? (i.e. as I was no. 1 on the list, I was assigned 1B, the first seat available based on my l-r, f-b theory).

G.S

Not that I ever got a CPU while I was still a 1K MM ... but isn't the effect exactly the same for revenue bookings? Whenever I book on the phone or via a TA and then log in to change the seats, I find my seats allocated like that.

From what I've seen it's first available seat with an empty seat next to it (1A->1F, 2A->2F,...) and then in the same order after that from front to back if there are no seats that meet this criteria. Window / aisle preference is ignored.

I have found that it fills from A->D from front to back, without regard for customer's stated preference (a common theme at UA). I tend to check at T-47 and T-23 if possible to see if I've been upgraded on those sweeps and reassign my seats to better fit my liking, especially when from the load factors it is clear I should be upgraded via CPU in advance of the battlefield.

Not been my experience - when I use my corporate TA they assign based on my stated preference (but admittedly that's from their systems, not UA), whilst when booking on the phone with UA, I have typically found they either ask me what seat I want or just completely fail to assign a seat at all (eg. applying an RPU over the phone yesterday, seat selection was just ignored and left blank until I assigned myself a seat).

I think it assumes that you want to get your preferred meal choice, and since PMCO FA's can't be bothered to follow the 1K meal prioritization policy, that means you need to be seated in the bulkhead!

So in a sense, it's COdbaUA trying to look out for it's most-valued over-entitled passengers!

Sort of. CPU processes in a checkerboard:

1A, 1E
2B, 2F
3A, 3E

and so on.

At the gate, all standby lists are cleared front to back with no regard to preference or E+, IME. So First will fill up straight front to back, left to right.

And coach will fill the same way. Even if you're on a wide open flight, they will fill up E+ first for no extra charge since the system can't start behind Row 21 for some reason.

You are wrong on the last part - they absolutely do clear standbys into E- now by default as part of the automated process. See for yourself next time you're standing at a gate with some time to spare. This might have been true at some time in the past but it's not true now. You can either look at the cleared standbys screen, or the seatmap itself.

So Jeffy Jeff likes to tout SHARES ability to price upsells by flight and by seat (is the reclining exit row window really worth $10 more than the non-reclining exit row window?).....

yet when the chips are down, it will give the house away for free!

That doesn't jive with my recent experience (< 30 days ago) when a non-Elite standby cleared into E+ right next to me, and there were tons of open seats in the back.

This issue is another reason I get annoyed when upgrades don't clear at the expected window. I know I have to babysit my reservation as long as upgrades haven't cleared because I fully expect to have to change my seat assignments as soon as an upgrade does clear. I know, a first world problem, but I truly do care about seat assignments. This system forces me to spend time and energy to get what I want--not very customer friendly.

Oh, and if the email notification system worked perfectly that would help some. I don't believe it does, though, so I can't rely on it.

Don't think I've ever received a notification of a CPU clearing and I'm at about 50% for instrument upgrades. Some system they have running!

Agent doing it manually? I've seen that happen a lot. Either out of laziness or just helping a customer out.

This is actually a difference between United and PMUA. PMUA didn't use to assign seats when a UDU cleared. You had to log in and do it. But now that there is an algorithm (front to back) that does it, two 1K companions travelling together on different locators have a much harder time of getting seats together because even if you log in right away after a sweep, the algorithm has already put pax in seats, and thus the cement has set.

The checkerboard pattern makes this particularly odd -- I've seen families checkerboard-ed across F.