DS>  I heard someone say in a railroad forum that Union Pacific operates
DS>all its trains on Central Time, since that's where their corporate
DS>offices are (I think they're in Omaha, Nebraska).

That is correct Union Pacific Headquarters is in  Omaha.

Some Trivia about Union Pacific:

They have 8300 Locomotives and 31,800 Miles of Track West of Chicago and
New Orleans
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