visa needed for 2 city stop over in china?

I am off to Istanbul but I have 2 stopovers along the way which are at Guangzhou and Urumqi.
Do I need a transit G or do I fall under the 72 hour free category? My transits are less than 12 hours combined in both airports.
I went to the Processing Service Centre who had no clue, told me to call my airline (China Southern) who had no clue and told me to call the Chinese Consulate who told me to call the Processing Service Centre.
This wild goose chase is sending me crazy.

I have an Australian passport
Any help and information would be appreciated.