Technically September for AMCAS, January 2025 for AACOMAS or even AACPMAS. To be "on time," recommended by May/June.
One awesome score at submission is generally better than waiting for a second or rushing to take a third. Some schools average scores during screening.
Plan for SJTs like PREview. Apply for FAP before taking the MCAT of your are eligible to fully benefit. Do not register for the MCAT without the waiver.