If I were you, I would definitely retake it on January, but I will submit my PharmCAS application ASAP, too. When I submitted mine on mid-October, it was kind of early phase of application cycle and since it's rolling admission, their standard for interview invitation was probably lenient I would say. Since you have strong GPA and experience, I would think you would definitely get an interview offer if you would submit application right now. But, 57% composite is not a competitive score in their standard, as they said 70% it is. Therefore, you should indicate them that you would retake it on January and you can just send them preliminary score report when your exam is done. I was invited to interview few days before my second PCAT on October, but I still send them a copy of preliminary PCAT score (99% composite) and it sure helped my admission decision after the interview.