US Passport Holder has more than 24 hours on return trip

Depart New York (JFK) with scheduled arrival Shanghai (PVG) Sunday at 19:30.
Then, Monday morning, PVG to PEK. Then, Monday afternoon, PEK with technical stop in NKG with no change of planes. Then, Monday evening, depart NKG at 19:30 to Sydney (SYD).

On return, depart SYD with scheduled arrival NKG Saturday at 19:25, with no change of plane. Then, NKG to PEK, with overnight stay in airport hotel. Then, Sunday morning, PEK to PVG. Then, Sunday evening, depart PVG for JFK at 20:15.

I assume that I will need an entry permit because I will be in China more than 24 hours on my return trip, even though I am not getting off the plane at NKG?