SAT or subject tests: risky scheduling

So I’m looking to apply to MiT, Princeton, Harvard, and some other reach schools like those. I want to make sure I’m considered for them, but my SAT is a 2140 AND I need to take 2 subject tests before I apply.
I got a 670 math, 740 CR, 730 writing. I figure math is usually my best subject, so I may have a shot at boosting it to 800 by my next attempt for a solid 2270. The problem is that I also want to reserve a test date to retake subject tests should I do lacklusterly. Here’s the scheduling conflicts:

June 6th: I want to take this SAT because it would leave the fall dates open for subject tests, but I fear improvement will be minimal because I haven’t practiced, and because I didn’t even think I’d do so well the first time. As a side question, would colleges frown on overall worse SAT scores on a 2nd try?

October 11th: This is a dangerously close date to the college admissions deadline. If I take the SAT then, I can almost guarantee a great math score, for close to a 2270 on my SAT. However, this would leave the Math II and Physics I subject tests to a single date on November. If I take these subjects today, I can retake them in November to fix potential flunks.

November: This is probably just a date for subject test retakes if necessary.

My idea was to just take subject tests in October, and if I need to fix my SAT I and my subject tests don’t suck, I can take the SAT during November.

I was wondering, would it really be necessary to boost my SAT to over 2200 to be considered for these schools? Such a goal is really taxing my resources, but I don’t know if 2140 will suffice.

Thanks

Why not take the subject tests in June? Then the fall dates can be used for any retakes if desired. (Also consider the ACT, which has different dates.)

I’m not very well prepared for the subject tests right now. I was hoping to study for them over the summer and do them upon returning to school. Taking the ACT sounds like a good idea, though.

Would you happen to have an answer to the first question? “Would colleges frown on overall worse SAT scores on a 2nd try?”. This is a particularly big one for my decision because I can still try to take the SAT this June and focus on studying for math in the coming weeks.

that depends on what each school’s policy is.
I think Brown just looks at the highest section scores while Stanford looks at all the tests you have taken

Wouldn’t the June date be the best for the subject tests in the subjects that you are just completing the courses for?

That seems logical, but I assumed I needed to prepare for the actual format of the tests and what kind of questions came up before I dove in. I wanted to take physics and Math ii because I can definitely prepare for those over summer well, but I just finished Biology and can probably try to take the Bio E Subject test. Am I wrong in that the format is an important factor when taking these tests?

Cannot help with what you should take in June but in making choice be aware of the following concerning MIT, Harvard and Princeton and all ivies. If your intent is to apply regular admission for freshman class of 2016, those accept SAT and subject tests taken through the January 2016 test date. If intent is to apply early action to one of them, they take through the Nov 2015 test date. All those profess that if you submit multiple SAT tests, they will use the highest section scores from the multiple tests to determine admission and not use lower scores against you.

You can try here for some practice questions:
https://sat.collegeboard.org/practice/sat-subject-test-preparation