9-1-1: Lone Star season 5 returns to FOX on September 23 after an extended hiatus, and co-showrunner/executive producer Rashad Raisani confirms that there will be a one-year jump, originally meant to coincide with the break between seasons. Filming was first delayed due to the 2023 SAG-AFTRA strike, and while it was expected to air in early 2024, the final batch of episodes were pushed to fall. The 9-1-1 universe has undergone several major changes over the past year, as the original show moved to ABC for its seventh season.

https://screenrant.com/9-1-1-lone-star-season-5-time-jump-explained/