Time “Sealed” → “Open” names the change in the state of time travel. Previously it was impossible, because time was completely sealed.
- The Opening Event: when and how it happened is unknown. A specific event caused the reopening.
- Implication: the group is in Antiterra before the events that triggered the apocalypse.
- Paradox: if time was sealed, how did Charlemagne already know he would have a time-traveling grandson? The answer given: a book traveled from the future to the past (a valid premonition without causation).