Re: How long should the new series go on for?
By then the cast of Justice League will be old and it will be time for a fresh reboot around 2030 after a Kingdom Come and Dark Knight Returns movie.
excluding DC projects not featuring Batman:
2016 - introduce new Batman in Worlds Finest movie
2017 - Justice League
2019 - Batman reboot
2020 - Justice League 2
2022 - Batman 2
2023 - Justice League 3 (trilogy ended)
2025 - Batman 3 (trilogy ended)
2027 - The Dark Knight Returns
2028 - Kingdom Come
2030 - reboot Batman and Justice League