Is it okay?

Hello I am going to Shanghai from Country A via Country B to China (5h layover), arriving in Shanghai on the 9th of a month.
Then I would stay until 15th of the month (4pm departure time) in Shanghai and leave to Country B via Country C!
The routing should be okay because it is Country B to China > Country C > Country B!
But is the time in Shanghai from 9th until 15th okay?
As I understand the 144h will start fon 10th from midnight - so I should be able to stay until 15th 11:59 pm, right?

Thank you so much!