A while back I was checking out all the novel statistics and settings for XP. That's when I noticed something really interesting.
Authors have the ability to designate a book's length. There are usually 3 options that you can choose from; Super-Short-Stories, Short Stories, and Novels.
I noticed that XP had been defined as a novel and there were no other options available to choose from.
So there you have it, confirmed by Webnovel themselves, XP is in fact a novel.