Oops - yes, thanks @mom2and - end of his JUNIOR year. My coffee is broken today. 
And @bopper has a very good point. S took the SAT the same day as the senior prom. I’m sure the prom was scheduled for that date knowing that none of the seniors would still be testing, but my son, then a junior, was (and is still) dating someone who was then a senior. He had a chorus concert on Friday night, SAT on Saturday morning, napped, then was off to the prom. Crazy day!