Likelihood of getting into Hotchkiss, Exeter, Andover, Loomis Chaffee, Groton as incoming senior

Hi. I’m currently a rising junior going to a charter school in Arizona and I’ve been considering applying to Hotchkiss, Exeter, Andover, Loomis Chaffee, and Groton to spend my senior year. The reason for this is that my school is one where well roundedness is hard to come by and I think I will find some good opportunities at a boarding school. Even though my school is known for its academic rigor, I’ve wanted to experience the unconventional Harkness method of teaching that is found at these schools. I also want to experience life away from home so that when I go to college, it will be an easier transition. Is the admissions rate for incoming seniors/pgs higher or lower than that of incoming freshman at these schools? These are my high school grades:
Freshman:
Algebra 2-A
Honors English Language-A-
Honors Bio-A
Honors English Lit-A
AP US Gov-A
Economics-A
Chinese 1-A
Sophomore:
AP English Language-B
Honors Chemistry-B
Pre-Calculus-A
AP Bio-A
Chinese 2-A
AP World History-A
AP Economics-A
Extracurriculars:
-School has no tennis team so I play USTA tournaments outside of school. I played Sectionals over the summer.
-Member of NHS
-Peer tutoring coordinator
-70 hrs of peer tutoring
-This was from 8th grade, but I got an “excellent” in a NYSSMA(New York music evaluation) solo for trombone
I know I am lacking in terms of ECs, but could you tell me the likelihood of being accepted to these schools? Thanks.

The likelihood of getting in as a senior is somewhere between slim and none. PG’s have a better chance, but are almost always athletic recruits. Top prep schools rarely take one-year seniors because of the steep learning curve/adjustment period that results when starting at a boarding school. Additionally, fall of senior year is when you have to submit most/all of your college applications, and nobody will know you well enough to write a decent recommendation. You’d be better off applying as a repeat junior, and even then, the admissions chances are only marginally better. However, if your goal is to experience life away from home, you’re better off just waiting another year until college.