Regarding the additional chapters for the "I Along Level Up" / "Solo Leveling" novel, see: https://www.reddit.com/r/sololeveling/
I found that some of the editted chapters have been consolidated in pdfs. https://www.reddit.com/r/sololeveling/comments/amk1vr/saturday_surprise_vol_5_and_6_pdfs/ Unfortunately, whoever did it didn't include the chapter #s. All I can say is that chapter 111+ is in pdf vol-6 which I'm rereading from now. I haven't finished it yet, so I don't know how many chapters it has.