If you are talking about the section of "Renegade" where it speeds up after the slow, more ballad-like progression finishes and Pedro and Karen begin their duel, then it's called "cut time".
Many rock and pop artists across the years and in many countries (as well as R&B and dance/electronic artists) have done this, but it first began in classical and traditional folk (Celtic) and Latin music. Therefore, I think it's no coincidence that "Renegade" has both Celtic and Latin flavors.
Another Yanni piece that goes into "cut time" to showcase the solo musicians is "The Rain Must Fall" as performed on Live at the Acropolis.
Cut time means that the song stays in the same time signature, but the chord progression happens twice as fast and the beat hits every two beats instead of every four.
I've played the song many, many times myself and that's the only section that I can think of that offers any drastic change, other than where it gets quieter before the melody repeats.
Hope this helps.
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