Taipei- Canton 3 days- Hong Kong is ok?

I am flying from Taipei ( 4 days) to Canton( i want to use the 72 hrs) then fly to Hong kong( final destination)

Then a week after, i would fly to Tokyo (4 days) - Canton (3 days / 72 hrs) - HongKong (final destination)

Thank you and advance for your cooperation.

I am an US passport holder.

Will this be ok in one month period?