Yes, it's the grades at the end of the junior year. So not automatic, but if he does the holistic review, they will consider his grades through the first semester of the senior year. Auto-admit is just getting your foot in the door. You still have to write some pretty solid essays and have your resume considered to get into your major or colleges other than liberal arts. My son was auto-admit last year, but the application process still was grueling because he wanted either Plan2 or Liberal Arts Honors. Thankfully, his major (history) wasn't one of the more competitive ones.
TLDR, not auto admit but don't sweat it. Auto-Admit application and holistic application are the same application at the end of the day. Declaring a major isn't like declaring bankruptcy anymore. You can't just yell it. You have to ask nicely, and they'll think about it.
/so there are two jokes here. The Michael Scott one and the more creative one about how declaring a philosophy major is, in fact, like declaring bankruptcy. There probably are more.