Even so, an AO can figure out where you are relative to the rest of your class. The reality is that your GPA places you in the fifth or sixth decile at your current school which will seriously impede your odds for Exeter (or any school at that tier) regardless if you apply as a junior or a repeat sophomore. That said, there are many schools that may love to have you in their student body and may provide you with the FA needed to attend. But you’ll need to cast a wide net. Ypu should read through the following thread for starters:
http://talk.collegeconfidential.com/prep-school-admissions/1545276-2013-14-hidden-gem-applicant-thread-p1.html
Good luck.