I know Baiyun Airport have a VOA counter. He has a valid passport, can he manage to get it there?

My boss going to china today (26th march), only to realize his visa has expired on 19th march while in the cab. He is going GuangZhou (waiting for flight now) and arriving around 9pm in Baiyun International Airport.

I managed to google that the counter closes at 5pm(GuangZhou time) what time do they re-open? 9am? I already told my boss he probably need to stay overnight at the arrival hall and wait for the visa counter to re-open.

Anyone can provide me more info to pass to him? thanks in advanced.