I’ve looked up the RAWs up to chapter 30, and well, the manga has completely diverged from the novel it’s based on. Honestly, only the beginning aligns with the source material. Many interactions with supporting characters were omitted — most of them weren’t even introduced in the manga. While the overarching storylines share some common points between the novel and the manga, they’ve been simplified, had their context altered, or were brutally condensed in the latter. Events from the most recent chapters didn’t happen in the novel at all and were created solely for the manga.
The novel is still ongoing, and it’s hard to tell whether it’s nearing its conclusion or only halfway through. This likely led to the decision to alter the events in the manga to allow it to conclude independently of the novel.