I had the same thing happen to me on a flight from SFO-PVG, and I got an "apology" email, saying "we are sorry you did not get your upgrade." I was first on the waiting list all day, then while boarding was still going on, number 2 on both the first and business upgrade lists (same person) was upgraded and moved to business. My itinerary on my mobile app showed me in business, but I could not refresh my boarding pass. I showed the purser who said not to worry, that I really was not upgraded. On arrival in Shanghai, I complained and got the aforementioned email, and it took three more emails and a fax to get my upgrade returned. The service reps kept arguing with me that I got my upgrade, so why was I complaining.