For several years, I was doing the SFO-PEK trip every few months. Was a great schedule, since the return flight arrived SFO early morning I could make a connection from SFO eastbound with no problem. When they shifted the overnight to ORD, they pushed the SFO return to early evening PEK departure, which made the arrival in SFO after lunch, which busted my decent connection options. Glad I'm not doing those any more.