3 day round trip to Shanghai from Hong Kong - Australian citizens

Hello, we hold Australian passports and plan to visit Shanghai for 3 days (arrive Saturday and leave Monday). Our trip is a round trip from Hong Kong. That is, we fly out of Hong Kong to Shanghai on Saturday and return to Hong Kong from Shanghai on Monday. We will not be visiting anywhere outside of Shanghai, Zhejiang, or Jiangsu. Can you please confirm that we will be eligible for the 72-Hour Visa-Free Transit?