Originally Posted by denCSA

FYI I had the same thing happen this weekend, and it worked beautifully on one of my flights.

I was booked LAX-IAD this weekend, in E- as a lowly *G. I had pre-selected an aisle seat in row 24 a while back at booking (737-800). 2 days out from departure I noticed that 23ABC were completely empty so I moved myself to 23C as 24B was showing occupied on the UA.com generic seat map. I wish I would have taken screenshots to prove this, but here's what I noticed at checkin time:

-Flight status seat map tab showed 23BC occupied, 23A open. 24BC open.
-UA.com checkin showed 23B as available for me to select.
-I thought this was interesting, so I had a friend check this in SHARES and he told me that 23B was showing 'Q' (I forget what he said the legend called this seat but it was something along the lines of preferential last offered). Available seats normally show as @ or . I believe.

Now, guess which seats were the ONLY two in E- not taken on the flight once the door was closed? 23B and 24B. Coincidence?

So, on my next flight IAD-DXB an almost identical thing happened. I was originally booked into seat 37D when I made the reservation, hoping the middle seat would stay empty. About 2 days before the flight I checked and the middle showed as occupied on UA.com. So I switched to 44D as that middle showed as empty. A day later 44E showed occupied. Called up my friend again and just as before, 44E showed as 'Q'. I switched to 35C at OLCI time as 35BC showed free. Again, afterwards the generic seat map tab in the flight status screen showed 35B as occupied and yet I could see it free when I went back through the OLCI process.

This flight was a different outcome, probably because it was full. Someone ended up in 35B, and looking back I should have asked him how/when he got that seat. If he got it from the agent, that would verify that UA is indeed soft-blocking these seats next to elites until no other seats are available.