Multiple stops with 24 hour TWOV

Hello,

I am planning to take the trip from Budapest-Ningbo-Guangzhou (with China Eastern Airlines) and then Guangzhou-Hanoi (with China Southern Airlines) and within 24 hours between landing in Ningbo and taking off in Guangzhou. Is this itinerary eligible for 24 hour TWOV?

How is the process when I land at Ningbo, there is only 1 hour and 30 minutes between landing and the next flight to Guangzhou so I am not sure if there is enough time for that (even this whole section is sold on China Eastern website).

Also, I saw conflicting statement online about multiple layovers at Guangzhou. "Transit including multiple stops within China is permitted at Guangzhou only when the first transit point is Beijing (PEK)." Do you know if this is true? If yes, then my itinerary is invalid then.

Thank you so much!