If you are scoring 170ish now, take the June. If not, how far off are you?
If you spend the next 6 weeks well, and can take an old real test every other day or so, you will be fine. the LSAT is definitely a test that you can get accustomed to. It rewards the diligent.
Spend the summer on getting your information together, reseaching likely schools, getting solid work exp, getting solid recs from profs, and then send out apps the day applications are being accepted by the schools you are interested in.
It's not just numbers, but if you have decent numbers then it can sometimes be a matter of getting in the door early. The application cycles have been getting absolutely brutal and show no sign of changing for the better. At this point, even sending out apps by Dec, can be considered too late.