A process, at a minimum, takes some time (dt > 0). Calculating the next state from previous state would be a process. If you make backups, you could also make additional calculation processes working from those backed-up states. Does that count as "creating more people"? That's a disputed philosophy of mind question on which reasonable utilitarians might differ, just like anyone else. But if they do say that it creates more people, then we just have yet another weird population ethics question. No more and no less a problem for utilitarianism than the standard population ethics questions, as far as I can see. Nothing follows about each individual's life having to have ever-increasing utility lest putting that person in stasis be considered better.