You can download a timetable from this United page:
http://www.united.com/page/article/0...tle=timetables

When you open the PDF (if it's still the January 2012 edition), turn to page 57, you'll see under Hong Kong that it operates daily, except for 1/21 ~ 1/24.

You may have done this already, but if you go to FlightAware: http://flightaware.com/live/flight/UAL895
In the Activity Log section, you'll see that UA895 HKG-ORD ran daily on and prior to 1/20. It has also been filed for 1/25.