I got an "op-down" like that on GVA HEL recently. I had my emergency exit booked on the E190, had quite a lot of food and drinks in the BA lounge, and then got a new seat assignment printed out at the gate, "op-downed" to business class, with a neighbor sitting next to me (as in economy), and less legroom. I got average catering I did not really need and more drinks which I did not need as well, the complimentary platinum gin&tonic would have been sufficient.