So I was picking seats today for my ORD-AMS UA908 (3/20), and was able to pick 23b. Now, these tickets were purchased from expedia, and it's marked as fare class S on the UA itinerary site. I looked this up in the handy booking codes thread:

S = Real Lowball coach with lot of restrictions. Reports that some are not mile earning ex UK/Brazil etc.

I'm also aware that non-elites (me) are unable to preselect E+ seats. How am I able to do it now? A day ago, the only open seats were in E-, and when something opened up in E+ I jumped.

Some more background, this is a 767-300, and according to the UA seatmap compared with one on seatguru, it's the new config. Any ideas? Will I just be bumped back to E- at checkin, but now without a preselected seat?

There are only five ways to get an E+ seat:

1. Have elite status on UA.
2. Be the companion of someone with elite status and on the same PNR.
3. Purchase a "buy up" for the flight.
4. Pay $299/year of E+ access.
5. Not have a seat assignment and assigned E+ at the gate because E- is full-up.

It has nothing to do with fare basis. If you were able to do it, it was almost certainly a bug on the website (very common). The computer does regular sweeps and will remove anyone from E+ who doesn't meet the criteria for being there.

I think there's a good chance you'll get put back in E- after a sweep, since you're not elite. So it becomes a choice between hoping to hold onto your seat in E+ but then risking an E- middle seat. There's also a possibility you could get E+ on the day of the flight if you didn't have a seat assignment at all if E- is full. Pretty risky, though. If you really want E+, think about buying the annual pass or hope you are offered a buy up at check-in.

Got it, thanks for the comments.

True.

But technically, the system should not even offer the E+ to a GM to begin with.

If the flight is only a few days out, chances are decent that the system will not pick up the fluke.

Quite possibly something is messed up with UA seatmaps related to new config.
OP, select E+ for now and keep fingers crossed, you may get lucky.

6. Have a gate agent take pity on you.
7. Be the beneficiary of a bug in United's IT.

Expedia will let you put yourself in E+ if you check some box somewhere that says your status entitles you to preferred seating or something like that. However, you will be almost certainly be reassigned an E- seat once UA does a sweep.

Note that fare class has no effect on your ability to select E+ or not. Full Y used to get E+ for free, but that hasn't been the case for years. The only way to get it for free now (legitimately) is to: be a UA elite member, be travelling with a UA elite member, or, being given the seat at the airport because E- is full.

If you picked the seats on expedia you may want to check the united website to see if you still have those seats or not.

Actually i was on the UA website when i was able to select it. I decided just to stick it out in the back with a window seat. I'll be sleeping so i won't notice...right?!

Sweeps don't occur often - it is well possible that the OP stays in the good seat.

A sweep (or at least one that altered my seat assignments) never occurred when I was somehow able to bring two no-status family members into E+ with me when I was still a 1P. You never know what .bomb will do...

But they happen when you least expect them and when they can do the most damage. Equipment changes also seem to trigger sweeps, and those are reasonably common these days.

Correct me if I'm wrong, but I thought a benefit of being 3P or above is tha ability to bring 2 guests into E+ if traveling on the same itinerary.