PEK-SFO. I was a Silver, flying on the cheapest possible ticket. Almost the last one on the plane, when my boarding pass was scanned it beeped funny and the gate agent said “UPGRADE” and shoved me into business class.
Unfortunately my wife was in the very back row, in the middle seat. I could not get the gate agent to even consider selling me the empty business class seat next to me, so I did the right thing, went back and sat next to my wife in coach, and gave some 19 year old kid my business class seat.
If she had been on the aisle seat, we probably would have swapped around halfway through the flight, but no way in hell was she sitting in the middle by herself for 12+ hours on a night flight.