I don’t know if this has been mentioned before, but I am thinking they wanted to make it clear August added to the book, and added stories of what really happened and is not trying to mislead Henry or Emma. (As an aside, I think he is trying open her eyes to what is really going on.)
In episode ten, “7:15 a.m.,” near the end, James encounters Red who tells him Snow is gone, and it appears then as if he turns to ride off directly after.
Then, as soon as Henry gets his book back in “What Happened to Frederick,” we focus on the book and fade to the same scene, but there is more too it, and Red ends up riding away from soldiers. This is an extended version of the same scene, and it implies that the new version of the book contains the longer version with more story.
I know the first scene was cut both for time and because the focus wasn’t on that part of the story, but on Snow drinking the anti-love potion, but I think a secondary purpose was to set us up for the scene in which the book includes new information, as a clue. I think this because we didn’t need that scene at all before seeing Snow and Grumpy in her bedroom. We just needed to see him leaving to find her.
This this is a not-too-subtle way of showing us the remade book includes new and/or extended information and maybe entirely new stories. I don’t know who August is or why he would do this, but it makes sense that’s what he is doing, especially as we saw him varnishing papers, which would imply he was making new pages.