Does anyone have advice on how best to use my remaining 15 clean practice tests and move forward with studying for the October LSAT?

Can anyone speak to whether or not performance in the experimental sections is a good / better indicator of performance on the LSAT?

I have been studying for the LSAT since June and I've been putting a lot of hours in (between 15-30 hours a week). I will take one LSAT in September (my first) and one in October.

I have 15 clean practice tests left. My scores are generally trending in the right direction, typically 165-167 with 170 on the blind review. (Target score is a 170 or higher).

I am concerned that my practice test scores are skewed by me remembering answers to questions I've already done or seen. I routinely get -3 on the LR sections which include questions from the curriculum, but between -5 and -8 on the experimental sections which don't seem to have questions included in the curriculum. I also spent a few weeks burning through drills which resulted in 25 untaken practice tests which each have over 30 questions that I have seen.

To be clear, I have 40 untaken practice tests remaining, but ony 15 that are clean. I have only taken the modern prep-tests and none of the obsolete tests.