In my latest game, to stop craver population in an occupied system from depleting other planets in the same system,  I sent all cravesr to a system with only two tiny planets on the other side of the spiral arm. 

Unsuprisingly,  the system turned full population long before the logisitics ships arrived the destination, (well, actually before I took over the craver system).

Later, I tried influence the stucked ships indirectly by adjusting destination of ports on both the craver system and the tiny system, the ships were still trapped outside the tiny system.

So, Is the game designed like this? or actually the logistics ships can be redirected in some other way after departure?

Thanks

Is it an legit way to dump undesired pops?