72 Hour Transit Visa Stipulation

I'm hoping that my 60 hour trip to Beijing will allow me to get the 72 hour free transit, but am concerned about my outbound flight's route. I have an outbound flight from the Beijing Capital International Airport to Istanbul, but with a stopover in Urumqi, China along the way, which I've read, means that I'm not eligible for the 72 hour transit. The outbound flight must apparently be direct into another country, and since I have a stopover in another Chinese city, I believe that I am now ineligible. Can somebody confirm this before I go ahead and purchase a regular L type?