Wife was op-ups DXB-IAD one time. This was well pre-merger. I wasn’t there, but apparently they called her to the podium, and don’t know if they told her she something like she had a new seat, or she just noticed it first, and was upset she was moved before she realized this was an upgrade. She was silver at the time.

Last year, as a gold, was on a UA-LH connections, flying to BLR. On checking in, so my seat was changed - But the UA-issued BP didn’t have the class on it. Realized I had technically been double-upgraded from regular economy to Business on the 748. So other carriers do that too.

Ive also been op-up’d several times on domestic flights both pre- and post-CPU/UDU - ORD-YYZ (And cvg), IAD-JFK and CVG-SFO (this past Dec.) are definitely a couple of times I remembered. The post UDU op-ups were on awards where I wasn’t eligible (have an older UA card, not the Explorer/Club), but still got upgraded anyway.