In VB6, there was a message (and interrupt) in the log for when a ship had Default/Standing Orders set but were unable to find any valid targets (e.g. when a geosurvey finishes every body in a system).
In C# there is no such message. Is this a bug? I've noticed that it becomes a big pain to manage multiple survey vessels, even with the new "move to system requiring survey" standing orders. For example, I have to frequently click through all the survey fleets in my empire to find which ones ran out of orders and are just sitting in space running up their maintenance clocks unnecessarily.