Thank you everyone for the replies. I saw a departing flight to PVG scheduled from one of the 520 gates. I assume these are bus gates since there doesn't appear to be any place for the plane there.
I guess we'll just have to wait and see what happens. If anyone has an idea of how long it would take to walk from The Pier to the 520 gates without stressing, e.g. just walking normally, that would be extremely helpful.