Kingdom of the Planet of the Apes is technically the fourth movie in the reboot series, but it's set much closer to the original Planet of the Apes films. Scheduled for release on May 24, 2024, the upcoming movie follows the events of War for the Planet of the Apes, which was the epic conclusion to the story of Caesar, who led the uprising of the apes and essentially sacrificed himself for his family and his species' freedom from the Colonel (Woody Harrelson). At the end of War for the Planet of the Apes, Maurice the Orangutan promises Caesar that his son, Cornelius, will know his name, hinting that Caesar's legacy will continue.
https://screenrant.com/when-kingdom-planet-apes-set-previous-movies-franchise/