GMAT Strategy

A little bit of background of past 3 odd months:
Target Score: 700+
Gave my GMAT last week and it was a disaster. I scored 640 (Q48,V28 :O, IR 6). Hugely disappointed with my verbal score. I am a non-native english speaker but I am not terrible at it. Even in any of my mock tests I did not score less than 32 in verbal and that was in my diagnostic GMATPrep test.

Background of my prep:
Quant - MGMAT Guides, OG13(twice), Official Guide 2nd edition, GMATPrep Questions. Few questions from 700-800 level questions collection
Verbal -
SC - Manhattan GMAT 2 times over + 1 quick revision - I do believe this is the weakest of of all 3 sections in verbal as quite a few times I am not 100% sure if I selected the answer correct even if eventually I did get it correct.
CR - Powerscore bible - I did OK in this section
RC - Practice questions only - Official Guides - I believe this is the strongest of my sections as I did consistently well in practice problems
I did OG13 and Verbal Guide 2nd edition 2 times for CR and SC and once for RC. During my first round, my accuracy was 60%-65% but during the round 2 it shot up to 80%.

Practice Tests:
GMAT Prep1 - Diagnostic - 650 (Q47,V32) - Not sure about the breakup but definitely Q was better
GMAT Prep1 - Retake after Maths prep - 660 (Q48,V32) - Not sure about the breakup but definitely Q was better
MGMAT 1 - 650 (Q43,V36) - Without IR/AWA
MGMAT 2 - 670 (Q46,V35) - With IR
MGMAT 3 - 660 (Q44,V36) - With IR
MGMAT 4 - 680 (Q47,V36) - With IR /AWA
GMAT Prep 2 - 700 (Q49,V38) - With IR /AWA
GMAT Prep 2 Retake - 750 (Q51,V40) - With IR/AWA - Around 12-13 repeats in maths section as I already did GMAT Prep questions, thus an inflated QA score but for verbal even the repeats didnt make much of a difference cause i didnt really remember the answer choices and all.

And then there was my GMAT disaster. I was very relaxed without being too relaxed so there were no exam day jitters leading to a disaster.

I am planning to retake my test and if anyone thinks I should not I am open to their opinions but I am more or less set on a retake. I have few queries to which I do not have any answer. It would be of great help if someone can show the way forward.

Q1. Is 1.5 months enough to improve my score to a 700+? I know this is a subjective question but still would need some inputs. Also, I can invest 2-3 hours on weekdays as I am a working professional.
Q2. I know I did very poorly in verbal. I did my research on forums and I did what I thought was best for the section but still did miserably. Now, I do not know how to improve in this section. I believe I was doing better than OK as my mock scores depict but still I scored a 28.
Q3. Any inputs on study plans for retake
Q4. Any other opinions/suggestions.

In anticipation...

Cheers