If your title has never been in distribution, any changes can be made to your title.
If your title has been in distribution, industry standard says only 20% of your book or less can be updated. Any substantial changes are not allowed, as they typically result in distribution issues. For example, changing from paperback to hardcover is not allowed.
*If you are updating more than 20% of your book, we recommend purchasing a new ISBN and setting up a new title on your account.
If your title has been in distribution and you only need to make minor changes, you may do so. Examples include updating a subject code, book description, or review quotes.