I got Op-Upd today at the Business Class lounge. I, flying to DEL, and this other lady flying to London, both asked separate agents at the same time. She was obviously Gold as well, considering she had access to use the lounge, but the lady who took her boarding pass came back saying that economy wasnt full so they weren't doing upgrades. The gent who was helping me told me Y was full on my flight to DEL, so they upgraded me to business.

So I guess, there needs to be an oversell situation at least for op-ups to happen.