https://stackoverflow.com/questions/2234121/can-2-timezone-b... has "There has been recent discussion on the TZ mailing list about the area of China known as Xinjiang, which has a mixed population of Han Chinese and of Uyghurs. It seems that the Han use the standard Chinese time zone (Asia/Beijing), but the Uyghurs often use a local time zone. This is now encapsulated in the Olson database, with the name Asia/Urumqi for the Uyghur time zone."
When I had T-Mobile Home Internet, my IP address would geolocate me to random parts of the country regularly. It was rare that it landed in my time zone let alone my state. It got really confusing for store websites because they'd try to locate me based on IP and serve me stores in Wisconsin while I live on the east coast.