Scored 680 -- Disappointed in my score

In a previous thread , I mentioned how my last practice test dropped significantly from the previous. This happened to instill a lot of nervousness in me going into test day. Scores are as follows:

MGMAT CAT 1 - 640 (q42, v36)
MGMAT CAT 2 - 640 (q44, v34)
MGMAT CAT 3 - 620 (q37, v37)
GMATPREP 1 - 700 (q47, v38)
MGMAT CAT 2 - 680 (q44, v40)
GMATPREP 2 - 700(q44, v41)
MGMAT CAT 5 - 670 (q42, v39)
MGMAT CAT 6 - 620 (q45, v31)

Unfortunately, that nervousness didn't transcend to a very great score for me. I ended up scoring a 680 (q45, v38, IR 5). I understand to most, this is a good score, but I was really gunning for 710+ (Ideally 730).

I completely blew Integrated reasoning after spending 4-5 minutes on a question that I realized near the end I was performing the wrong calculations. On Quant, I thought I did decently for the most part, but I ultimately had to guess on the last question as I had a minute to do that. I was quite shocked at the verbal score since I finished it on time and didn't think the questions were overly challenging.

I started prep back in February by taking an in-person MGMAT course. It was great. The course ended mid-Feb, and then I proceeded to do self-prep for 2 months. In hindsight, that was a bad idea since I feel that my performance peaked back in Mid-may. In June I saw myself going downhill.

Given this, does anyone have any retake strategies? I will most likely take a week or so off to decompress, but will ideally start prep on or before July 4th for an August 1st retake. Does a month sound like a sufficient amount of time for someone who wants to improve 30-50 points? Longer? Shorter? (I intend to apply round 1 this fall). Ideally I would study 15-20 hours a week. I took all the MGMAT tests, so I probably will have to purchase some new CAT's for my new prep. I want this prep to be different and more focused on my weaker areas so that I can improve. I developed an error log as I worked through CAT's and OG problems; however, I wasn't religious about reviewing it. I made flashcards, but they were only of concepts rather than any focus on a particular question. I've went through most of the OG2016 questions and did a decent amount of Quant Review 2016 questions.

Additionally, I did not cancel my score at the time because I wanted to sit and think, but I most likely will pay the $25 fee to cancel online. I'm assuming the schools I selected won't see that score right?

Thanks!