Sorry, I'm also a little confused and a little stressed at the moment.
He will be going through Guangzhou in China, I will ask him to call them tomorrow, I have also found the number to call from the US, so at least I know the next step. Hopefully they can extend the expiration date due to some extenuating circumstances (the embassy is rather far from where he lives but is the only one in China that processes K1 visas, and he recently had a medical procedure that may limit his ability to fly/sit for long periods).