The rules we are considering all have the property time is slightly less simple than one might imagine. In a CA, we think of time as an integer. When time becomes the next integer, the new state is modified from the old state according to the rule; otherwise, nothing happens. The sequence of states has a one to one correspondence with the integer time states that correspond to the sequence of temporal steps. The idea of time with 2 distinct phases is due to Norman Margolus. Our concept is a generalization of that idea. We will illustrate how perfect CPT symmetry of the physics can be achieved in a RUCA with 6 phase time. What will be explained in detail is exactly how the simplest possible T symmetry of the DM RUCA gives perfect CPT symmetry of the physics being modeled. Always remember that if any RUCA can emulate physics, every RUCA can. That means that 6 phase time is not necessary but we believe that it is economical.
