Many people on Chinese flyertalk claim the op up order nowadays to be all MP elites > oneworld elites. This was actually validated by someone claiming to be CX ground staff @ JFK to be true. (I'm sure you will see replies stating that they have seen otherwise, but YMMV). It has since gotten even more complex with the ACV scores and all that. Well, it's not surprising that GR gets opups sometimes. Plus with 4 flights a day, it's unlikely that every single flight on every single day of the week would be elite heavy.