China used to have 5 time zones before 1949. Now it has only one. Urumqi is 2 hours behind Beijing since it is situated on the westernmost part of China. Most locals follow their own unofficial Xinjiang time according to the dictate of the sun rather than of Beijing. They start work or open their shops at 10.00 am Beijing time. Some buses also use Xinjiang time. The government departments run on Beijing time.
Therefore, when in Xinjiang ask not only what is the time but what time it is.
I guess one reason why the locals prefer Xinjiang time is because it does not get dark until late in the evening. It may also be their subtle protest towards Beijing.
8.49 pm Beijing time
9.20 pm Beijing time