Each injury initiates a different solution, and the CA move upward at different velocities. The smaller the CA the faster it goes. v = f[size, injury]. Suppose that the CA starts cruising at f[19,1] (1 means that only one cell was injured) . It may now accelerate its velocity by activating f[13,1], or f[11,1].
In the next image the CA started cruising upward at v=f[11,1]. At t=150 it started injuring its upper cell, leaving the lowest intact, and headed downward.
You may now examine this behavior in the following applet