If you are planning on going to Bschool soon, it might not make sense to leave a job to just start another one and not have enough time there either. Too many jobs in a short amount of time does not look good, and will mark you are a "jumper" or something that doesn't knwo what they want to do. Since you've already jumped so much, it might make sense to see out the rest of your term there, and then move onto Bschool. The only reason why I wouldn't do this is if you are able to land a significantly better job. I would not recommend that you quit before you have landed another job though.
You have a strong application, so don't let your dislike for your job overshadow the rest of your strength.
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