It's called j_dolphin style, one of the oldest styles around. Plus there's a Real Drum track called bossa/swing. Check out the Bars edit window carefully. You can change styles, tempo's, change the RT/RD/s on a bar by bar basis as much as you want.

Changing the number of beats in a bar is called the time signature so changing it from from 4/4 to 3/4 or whatever is done by changing the time sig for that bar then change it back at the next bar.

Bob

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