When does Jeremiah return?

The series takes place in a future wherein the adult population has been wiped out by a deadly virus. The year is 2021, 15 years after a plague has killed nearly everyone over the age of 13. The eponymous Jeremiah is a semi-loner who has spent the last 15 years travelling back and forth across the United States, seeking out a living and looking for a place called Valhalla Sector. Jeremiah is searching for the "Valhalla Sector" where his father may still be alive.