Unfortunately, the official China Post tracking website is Chinese only. You probably checked on one of the few third party tracking websites that use automated translation (or for the better ones a custom database with proper translations) to display English messages. I can't just use the results of such websites (they are trying to make money with it from ads) and I currently cannot offer a translation myself (doesn't make sense with my current monetarization as all translation services are paid by volume of translated characters).