He died then. Verse 31 is helpful.
Passover, the 14th, was the Preparation Day for what? For the 15th day, which of course is the first day of Unleavened Bread, and the first day of Unleavened Bread is a holy day. It is a Sabbath.
It is interesting that John then inserts, parenthetically, "for that Sabbath was a high day." Now why do you think he put that in there? He put it in there so that anybody reading through here would know that the next day, though it was a Sabbath, was not a weekly Sabbath. Everybody got that?