Older saves might have that issue still , but I did play test just now the segment you mentioned so I didn't have any issues?Yes, I've had this bug happen before like 3-4 versions ago where instead of new content (if there was any), my game would load old chapters and confuse me.
Now it happened again, I don't know what's new but continuing from last version's save at the end, the game sends me all the way back to the scene with Kiara in the bathtub (get more comfortable with Natsuko or tell her to wait choices).
First choice :-
Second choice :-