How do Future Events work and what happens when the Current Events deck runs out?

Question

Accepted Answer

When Current Events run out, shuffle the Future Events pile and sort it so older Age cards sit on top. An event you add to the Future Events pile scores any victory points at that moment, not again later. Future Events from earlier Ages stay in the pile when an Age ends, and drawing from the military deck doesn't produce current events.

Through the Ages: A Story of Civilization

How do Future Events work and what happens when the Current Events deck runs out?