Complex sentence: The livery phases appeared as different designs with a majority using a red, white, and blue (the colors of the American flag) format, except for promotional trains, state partnership routes, and Acela "splotches" phase.
Split into simpler sentences: The livery phases appeared as different designs with a majority using a red, white, and blue (the colors of the American flag) format. Except for their promotional trains, state partnership routes, and Acela "splotches" phase.