I am travelling to see my cousin in Guangzhou and just want ot check on the 72 hours stay.

I read on your website that "For example, if an air passenger arrives in GZ at 08:00 on June 2nd, then the latest time for him to leave is 23:59 on June 5."
I will be arriving on Aug 18th at 0525 and will be leaving on Aug 21st at 0930.
Will this be ok for me to book without applying for a visa?
Also, I will be staying at my cousins, I will need to provide the address but will there be anything else I need to provide?
Many thanks in advance for your help.
Warm regards,
Damian