it seems if you get any levels between chapters you are reset to a lower statset when you go to the next chapter
Viewing post in Goblin Layer (NSFW) comments
playing normally, leveled up a little bit in first chapter and when i went back after getting the other two members i was not at the same stats, i noticed because i used to overkill everything then i was not. and when i loooked i went from i think 90 atk to 75 (using steel sword) but for whatever reason the level and hp seemed like they did not change