Do you know if it's possible to make a fixed-layout ePub which displays one page everytime in iBooks regardless of whether it's in landscape mode or portrait mode?
It looks like a combination of <meta property="rendition:layout">pre-paginated</meta> and <meta property="rendition:orientation">auto</meta> should do the trick.
cf. http://epubsecrets.com/fixed-layout-in-epub-3-0-draft-metadata-property-definitions.php