How do I animate a node using a driven key for part of the animation, but then switch to 'normal' keyframing at a certain time position ?

For example, if I animate a bouncing ball, I might want to drive a squash value using the ball's translateY attribute. If the ball comes to rest after a few bounces, though, I then want to animate its squash value using normal time-based keyframing from that point onwards. Later on in the animation, I may then want to switch back to using a driven key.

Is there a way to do this ?

Many thanks

Steve