Thanks for the inputs, but I'm getting more confused about this. Here a basic example that clarify my interrogation:
AA and BB are two inhabitants of NPMR(k) and are both planning to incarnate in PMR(k). BB tells his friend AA that he'll incarnate first to see what kind of experiences they can get in this PMR. So AA will wait until BB complete his first trip to PMR(k). BB lives 70 years in PMR(K) and die. He's now back in NPMR(k). From the perspective of AA, how long this process took?
This scenario works well if you imagine two PMR-based entities outside of PMR talking about going into PMR - but it starts to break down when taking into account that the consciousness of an NPMR(k)-based entity could very well transcend the entire chronological framework, rendering the perception of time (not time itself) in NPMR(k) less meaningful than it is here in PMR.
Also - I'm not sure it is safe to assume that time only ticks forward in the non-physical environments. I don't doubt the existence of the forward motion of time in environments beyond PMR, but I also acknowledge the possibility of a backwards running motion of experiential time, as well as a sideways one, and/or an ascending or descending motion of sequential events behaving within dimensions we can't imagine. There are fewer limits in other words than exist in the NPMR(k) scenario described (when compared to how time behaves in our PMR) as far as time is concerned, a wider range of perceptions available to the non-physical observer then has been ascribed to AA and BB, and any account of the perception of time - Tom's, mine or anyone's - would be subject to the level of perception of the observer.
If AA and BB are time conscious efficient types, they should simply feed the data inputs governing the type of experience they want to have at what time/location within PMR-space into the Future Probabilities Database and see what sort of report that spits back. Curiosity satisfied, they could then move onto some other curiosity. Or, they could simply merge for a while into a single unit of consciousness and experience the incarnation together. That'd be fun :)