I’m confused

EPUBs not updated?

Why are EPUBS not updated? I have several O'Reilly ebooks, and receive update notifications when they are updated. Without exception, the update notifications indicate that more than one format has been updated, say PDF and EPUB, the two formats I'm interested in. Sometimes MOBI or another format is included in the announcement. But only the PDF is actually updated. Why is that? Most recent occurrence, Learning Python 5th Ed. EPUB file size is same as before, and checking the errata shows no updates for EPUB, only PDF.
1 person has
this question