If you change your mind about the size of the book you'd like to make in BookWright, you can always adjust it to a larger or smaller format.
1. Open your book in BookWright.
2. On the top menu, click on Papers/Format > Convert Book and select your new size.
3. Your project will now be saved in the new size.
If you would like to upload your project in multiple sizes, it's best to first save a copy of your book by going to File > Save As and then saving each book size with a distinct name, like "Barcelona Holiday, Large Square" and "Barcelona Holiday, Standard Landscape."