I believe that all of UAL's 777-200A's (non -ER's) have 2 classes, and serve domestic routes including Hawaii. The -ER's have PTV's, and fly the intl. routes, and maybe some domestic runs for aircraft positioning purposes.
A large chunk of United's 777s are non-ERs. N766UA through N780UA are non-ER with three classes of service. You will find these crawiling around on domestic routes as well as east coast-Europe flights.
The 777-200ER birds (27XX and the 28XX series) fly mainly from the west coast United States to Europe as well as to Asia. The 28XX series runs routes such as ORD-PEK, JFK-NRT, and so on.
Only 5 or 6 planes are in the two class config. I believe that they are 2510, 2511, 2512, 2513, and 2515. I think that there is one or two more. I'll try to find out.
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