Well, nowadays, what's the definition for upset?
Just before last Denmark open, Zhou Mi was ranked outside top 50 maybe due to her only two tournaments presence. She was always behind Ruina until Japan open. If upset means lower ranked beats higher ranked, then Camilla are always making upsets.
In the simulator matches and training matches just before the WC, Gong Ruina did pretty well while Zhou Mi one of the worst in the China national team.