They went back in time because one of them died in 1 and 2nd timeline, so this is the third timeline and «final» chance. I’m guessing they both want each other to be alive, and that’s why they went back in time. And in those timelines J already realized his feelings- I think.
Mioru bitch be missing hands and legs cuz of Kayden lol ٩(๑❛ᴗ❛๑)۶
Not only the limbs, but also the soul, I guess HAHAHAHAHAHA