Happened with my second chapter...
Though I am at least B2 (officially), it isn't my first language, and I tend to use past tense verbs when I already used "did" (did posted, did forgot, did spotted), but I rushed to finish said chapter in a week or two and I even had some blank spaces where color should be, layers I used for skeletons that should have been invisible and even duplicated pages.
Had to update it two times the same day, both here and in my blog.
I think most of these errors were corrected last chapter, but a man is not perfect...