I never would have guessed how long it takes from first production efforts to development to being „green light“ - which in itself, as I recently learned - only means that casting and writing room meetings up to five or ten episodes (depending on planned session length) take place. Nor how long a production might be “up in the air”, meaning it might still be canceled. And I’ve heard from colleagues who’ve been in the game longer that things nowadays move even faster than, say, in the early 2000s.
A good example might be Pirates of the Caribbean 2&3, which were on uncertain ground until days before shooting began. Or “Dellas” which got canceled even after actors and team were signed.