Does the 72h rule apply?

Hi,
We are planning to fly from Helsinki to Shanghai, then 3 days later fly from Shanghai to Hongkong for a day and then back to Shanghai for one day before returning to Finland. Does the 72h rule apply? Can we use it twice during this short timeframe (first from Helsinki to Hongkong with a three day stopover in Shanghai and then back from Hongkong to Helsinki with a one day stopover)?