I agree with what others have said with regards to timing, but I would caution you against being "insanely confident" about anything. Many have been burned before with that type of mentality, not just for medical school applications, but in training and actual clinical practice.
Bottom line is that you should not take the MCAT until you are ready to take it. If that means mid-June, then take it in mid-June. However, keep in mind that in order to have your primary application be verified by the time your MCAT score comes out in mid-July (most ideal situation), you will need to submit your primary application around the same time of your MCAT, which means you will be studying for your MCAT exam and preparing/submitting your primary application around the same time.
This is not ideal. So make sure that you are minimizing your extracurricular commitments for the next few months until you finish submitting all of your secondary applications. You need to treat the MCAT studying and application process like a full time job.
What this would look like (if you pursue this route):
- Now until end of May - work on your primary application and also MCAT studying
- Beginning of June until mid-June - focus more heavily on MCAT studying ("final sprint") while still looking over your primary application
- Mid-June - take your MCAT exam
- Mid- to late-June - finalize your primary application ("final sprint") and then submit it to one school (to start the verification process)
- Late-June until mid-to-late July - look over secondary prompts for the schools you are planning to apply to and start drafting your responses.
- Mid-to-late July - your score will have been released, and if it is satisfactory, send your primary application to the rest of the schools on your list, and then submit your secondary applications when they are ready, ideally by mid-August, but no later than Labor Day as LizzyM says.
If this looks like a lot, it's because it is (and if someone doesn't think so, I would again gently caution against being too confident). Many people try to do this and end up doing both mediocrely. So you do need to be very honest about your capabilities and discipline.
If you cannot realistically commit yourself to this schedule (and do both well), then it may be better to focus on the MCAT this year and then have dedicated time to prepare for an early polished application for the next cycle (2025-2026). Just my thoughts.