"If you only read the books that everyone else is reading, you can only think what everyone else is thinking."
You cannot perform a Passage of Time while the Operations counter is in the top three spaces. These spaces are marked "Cannot Perform Passage of Time" as a reminder.
Once the Operations marker gets into the numbered spaces you are allowed to perform a Passage of Time. If you choose to perform a Passage of Time then no die roll is required. If instead you perform any other action (Culture, Planning or Take Actions) then once you have completed that action then you move the Operations marker down one space and you have to roll the die. If the roll is equal to or less than the number of the current space then you move the Operations marker right down to the bottom space marked "Must Perform Passage of Time". As the box indicates your next action has to be a Passage of Time, and you cannot pick any of the other actions.