When I click Guard or Sentry for a ship or fleet, I can't tell that anything happens. I see that the appropriate boxes are checked in the Ship Details screen, but when I click the Find button, it keeps cycling back to the ship that has Guard or Sentry checked. It doesn't let me just forget about those ships, or at least put them at the end of the turn cycle.
Is it supposed to work this way, or am I missing something?