If your book is a read aloud book, you must indicate pre-paginated in the <meta property="rendition:layout"> tag in the <metadata> element within the OPF file. (See Defining Book Layout Metadata for instructions.) Read aloud content requires a custom sample. If you do not provide a custom sample, the book won’t be accepted to Apple Books. To create a custom sample, create a separate .epub file that includes the pages you want in the sample and deliver it within the <assets> block with type="preview". See Apple Books Metadata XML File Annotated in Apple Books Book Package Specification for more information.