AI Activity Cycles?

[OberonDark]

Just a quick question. I've noticed that sometimes I have ships doing absolutely nothing, and then all at once they all jump to go do some mission or another (all automated, private, etc.). This usually happens directly after I recieve some request from the AI on whatever I've automated, generally shipbuilding. I've noticed with my fleets too, they may have completed a mission, but they'll sit there doing nothing for a while, still saying they're completing the mission.

Does the AI operate on a cycle of activity where it checks to see what the ships are doing every few minutes or so? Because I never see a ship that's constantly active.