July 5.

Each day of validity ends at 23:59:59

It's a common question and point of misunderstanding. But the days start and end at midnight. So if you activate your pass to use immediately at 6 PM on June 29th, your first "day" is 6 hours long. But if by chance you are riding the train before midnight at the end of July 5th, you can keep riding past midnight entering into July 6th, provided you don't get off and leave the station. Very few trains go past midnight though and none of the bullet trains do.