Most of the PhD programs I am applying to have December 1st application deadlines. A couple of them stated that taking the GRE before November 1st will allow enough time for the scores to post, and for admissions to review them before the application deadline. I am pushing the envelope: my GRE retake date is October 30th. As long you take/retake the GRE by then you should be fine. Best regards & hope your seams hold up.