[Taqwus]

You might also store the number of turns required based on the previous province ownership values to reach the destination. If based on a new turn's ownership values there does -not- exist a path through friendly (or flyable) provinces that takes one or more fewer turns then that estimate, then one of the following must be true:

* The army has slowed down; possible if the player has assigned slower troops to it, or if it was flying and a global storm is in effect, or so forth.

* Previously efficient paths are no longer passable; perhaps the previous route included a province which is now hostile and the army can't fly, or an underwater province and Thetis just got dispelled.

In either of these cases, warning and canceling might be reasonable.

Actually, we already know that the movement order could store an associated destination in the turn file because it already does in the event that the movement takes just one turn. The only differences, if we ignore the above suggestion about times, are that the destination be interpreted as take the fastest route to this province even if we can't reach it in one turn instead of move to this province; and that the movement order be preserved for the next turn if not preserved. *shrug*