Thank you for translating.
I wonder if he will go back to the past again or whether it will be like that other time travel murder manga Boku Dake Ga Inai Machi where he has to finish the investigation in the present?
The problem with time travel and time loop mangas is that if you let the main character time travel too much then it becomes an unfair advantage for him and feels too easy and trivial.
The murderer has a book of future events around the elementary school case and knows of the existence of time travel (or at least supernatural foresight) but besides that is a regular dude.
I expect the MC will time travel again at least because it would be pretty bleak for him to just accept that his baby has been killed and wiped from existence.