spy's timing question

[marvin]

Is it the higher level of SPYING you got, the longer your spy can stay inside hostile countries?!?
Or no matter what level you got, they can stay there 24hrs max, as long as no people catch them?

[Nebthe]

24 hours, no matter the level. After 24 hours the spies vanishes. (after watching the enemy for 24 hours he surely notices that there is always a good pub there  )