Always order a proof copy, LOL. There's nothing better for finding a freaky error than holding the print copy in hand. I notice it now in the digital preview, but never thought to look close. So... here's what happened. The setup... In your book design you have your margins setup so the interior margin (into the bind... sounds like sword fighting now!) is larger than the exterior margin, otherwise, your text can begin to get "swallowed" by the curve of the pages and often the binding process itself. Well! I laid this sucker out with InDesign and everything looked perfect, except it isn't once compiled into pdf. The first page of the book is a "right page", seeing as it isn't printed on the back of the cover... good so far. The issue cropped up where Eve of Snows transitioned from "Front Matter" into the main book, I THINK because I then repaginated at 1. Hence, InDesign showed me page #1 starting on the right page, but when compiled into a pdf it went to the left page because the front matter ended on a right page... but the margins stayed the same, which FLIPPED the skinny outer margin into the middle of the book on the entirety of the book's text. So, when opening the book in person this error became obvious... still readable, but awkward. The other possibility for the cause is that I created the Front Matter after the Chapters, but I'm pretty sure it was starting the main text at #1 that stopped InDesign's automated syncing system from putting things on the correctly margined master page.