In A New Kind of Science, Wolfram shows that the sides of the generating system no longer continue the ruleset. Because the edges are not infinitely wide, the rules are stopped on the sides.

The effect of this is that you will not be able to start at a later part of the sequence and reverse engineer to the original starting point exactly. The lost data across time makes this impossible to do.

This is why SHA Algorithms Irreversibly Compress Data as well.