72-hour free Transit policy with China Southern Airlines

I land in Guangzhou and will have a 3 day stopover there. The total hours of my flight ticket from when I land to when I depart is 74 hours. I know this complies with the Guangzhou airport policy but was not sure if China Southern Airlines will have the same rule. I have valid and confirmed tickets with them though. Do I still need to apply for Chinese Visa then.