17 December 2024: J.K. Rowling replied to someone on Twitter/X saying she was tweaking the plan for Strike 9 and jotting down ideas.

28 December 2024: J.K. Rowling replied to someone on Twitter/X saying that she had begun work on Strike 9.

25 January 2025: J.K. Rowling updated her Twitter/X header to a photo of York Minster and the city wall and said that it is a Strike 9 location.

5 April 2025: J.K. Rowling changed her header to a photo of a treehouse.

18 April 2025: J.K. Rowling changed her header to a photo of some creepy dolls.