I think the Zhengzhou group has to make it to HK/Incheon before getting on a plane to Anchorage so it might be one of the flights leaving in 15-20 hours or so?
Flight from Incheon
Flight from Hong Kong
Looking at one poster's tracking from last year -- his had a departure scan from ZhengZhou directly to Anchorage. There is no departure scan for any other airport. It's getting a bit confusing but agree that we'll see a departure scan in 11-12 hours from somewhere. Maybe they are in ground transit to one of those airports. I can't keep track anymore lol