My best op-up was on United as a Premier Gold on an S Fare. SFO-TPE, Upgraded because of massive oversell in Economy. Long 14 hour flight, was dreading sitting in the back.

Got a nice op-up last year on LX on ZRH-DXB. K fare; had paid for a bulkhead seat assignment. Ended up with a business class seat approximately 18 hours before departure; the previous day’s ZRH-DEL flight had been cancelled, pushing a lot of the passengers on my flight.