It may also depend on how the airline checks status. When I got to *G with Thai, it still showed *S on the boarding pass of my next flight. Online, it showed that I had enough miles to get *G but I was still listed with Silver status. I asked about it in the Thai lounge (also had SK *G) and was told that Thai upgrade people at the end of the calendar month. As I got to *G about 5 days into the month, I would have to wait a few weeks. The agent in the lounge was able to see how many miles I had and was able to confirm that I would get Gold status.

If I didn't have SK *G, I probably could have persuaded the agent to let me into the lounge based on the info on her system. That was in Bangkok though where I assume she had direct access to the Royal Orchid Plus database; I'm not sure how well successful I would have been outside Thailand...