Publishing a blog any time can work to your benefit. If you create your blog as you’re writing the book, you have an online notebook where you can try out and refine content. Blog posts can be held as drafts indefinitely, so you don’t need to publish them until you’re ready. When you do, you can promote them in a variety of ways and generate comments that may help you think about possible improvements.
After your book is published, your blog is a great promotional tool and a way to interact with readers.