As for knowing all my plot lines before I start writing a story, no, I do not. Like you I have the basic outline and a way to start, but I develop most of the plot lines during the writing. I jot down my ideas just ahead of the body of the story, as well as new characters I want to introduce, new settings, etc. I love writing stories, many of which are based on places where I have been or even where I have lived. Thank you for your response.
Paul