There is a RealDrums called BossaThenSwing - it does that. It comes with styles like "BossaThenSwing" (-BSTSW.STY)
Of note, notice the drum fills going from A to B, and B to A - they are specific, and different than fills going from A to A, or B to B. This is on RealDrums Set 10 http://www.pgmusic.com/realdrums10.htm

http://64.40.109.185/pgmusic/audio/rd10/BossaThenSwing-1-Sticks_145_Demo_realdrums.mp3

BossaThenSwing
Time to switch things up! This fantastic new style provides a straight-eighths Bossa for the A section (either brushes or sticks, your choice!) and then switches to a cool Swing for the B section! Plus, with the new intelligent fills feature introduced in Band-in-a-Box 2007.5, you'll always get the perfect fills that transition between these two different feels. Here are some of the BossaThenSwing variations you'll get with RealDrums Set 10:

BossaThenSwing^1-Sticks_145 -
BossaThenSwing^1-Sticks_220 -
BossaThenSwing^2-Brushes_145 -
BossaThenSwing^2-Brushes_180 -
BossaThenSwing^2-Brushes_220 -
BossaThenSwing^3-Brushes,Sticks_220 -
With RealDrums Set 10, you get all of these BossaThenSwing variations!

BossaThenSwing^1-Sticks
BossaThenSwing^2-Brushes
BossaThenSwing^3-Brushes,Sticks

Have Fun!
Peter Gannon
PG Music Inc.