One of the “rules” of the 3by3 Writing Method is not to retreat and revise until the draft is finished.
On the other hand, many writers start off on their journey in one direction and find that their book has taken a turn and an entirely new story emerges.
The 3by3 Writing Method strongly suggests making notes about revisions and continuing on, after modifying your original story description.
The only time there should be a complete retreat is if the current book is basically going to be scrapped and a new book started. Here is a quote from the 3by3 Writing Method – Book One: Planning, Writing & Completing Your Novel about being distracted in the middle of writing your novel.
“Wanting to write a different book – the beginnings of distractions
You are halfway through your book, working on the middle chapters, which are often the hardest to create. You are not full of that initial excitement like when you first began, and this is not the drama-filled ending that you are working toward.
Then it hits you – it is a great idea! It’s a book about a masked skydiver who is an international spy and wine connoisseur who falls in love with a pacifist librarian who hates drinkers and airplanes.
This is a trick. A new book is exciting because it’s new. If you really like the concept, write it down (not during your writing time) and file it away for when you are looking for a new idea. Do not stop writing your current book. This type of distraction will always show up when the writing gets challenging. Do not fall for it.”
If at all possible, get the entire draft done as many ideas will come to you as you write, but constantly returning the early chapters is a temptation to resist.