Flying to PEK from ORD, which is also notoriously hard to upgrade, C was oversold by 7 on a 747 and I along with about 8 others were still upgraded at the gate. That means either that there were some no-shows or that Y was oversold and F wasn't so Y-C and C-F upgrades happened so no one would be bumped. If it is scenario 1, however, there is still a chance.