Episode 10 spoilers.
Unspoil at own risk. No, i'm not posting credentials
Jack gets his original sword back from ghost Scotsman, uses it to defeat Aku. Ashi starts dying. She creates a time portal before the final blow is struck. Jack does indeed go to the past, but instead of going back to his childhood, he goes back 2 hours and kills Aku at his base, saving Ashi. Scaramouch is also conveniently saved