It depends on how the AI of the game 'sees' the assignment. I haven't figured out the logic of this yet. Sometimes I get a Complete (and secondary assignment) as soon as I get within 50 miles of my patrol star, sometimes I have to float around it for several days before it completes.
Here's what I do: Use the compass tool to draw a 25 mile circle around your patrol star. When you get there, stay within the circle until it completes. You might draw an additional 50 mile circle around the patrol star. I think the actual diameter is 50 miles as I sometimes get a completion just reaching that point. You might also send a status report when you reach your patrol star.
By the way, its perfectly kosher to sink any enemy vessel you come across on the way to your patrol area. There have been a couple of times that I had to return to rearm long before I reached the patrol area.
Run Silent, Run Deep
__________________
|