Fallout season 3 will start filming next summer if all goes to plan, as its showrunners want to keep their big iron in the fire
They might not have committed to making any New Vegas ending the canon one, but the folks behind Amazon's Fallout TV show have been quick to decide they'd like to get started on filming a third series as soon as they can. Summer 2026, if all goes well, so the radioactive glow of the imminent second series hasn't totally faded to background levels by the time a follow-up drops.