Thanks all -
It was a hell of a month, and I went through lots of negative feelings. My original date of the exam was 12th December, but due to work pressure, had to reschedule to 7th April, then to 18th August, but in June-end , I got the following scores and pre-poned to 1Jul:
GMATPrep 1: 730 (Q50, V38)
GMATPrep 2: 740 (Q50, V39)
My mistake was not practising tests other than GMATPreps, and trying a bit too hard. But after getting these results, I pre-poned the test. However I scored only 660 (Q49, V31) AWA 6.0. While QA was a bit down, I had drastically underperformed in English. I realized timing was a big issue – I spent over 5 minutes in some questions, thus rushing through the end.
I did not study for the next 15-20 days, and tried to get back to my normal self. Tried deep breathing and meditation, watched movies, concentrated on pending office work. Then, took MGMAT test subscription as I knew one has to practice from external sources and also increase my concentration level.
I did not touch OG/OG 11 at all. Did practice a few questions available here and there on the internet, and took the MGMAT tests. My scores were:
MGMAT1: 710 (Q48, V39)
MGMAT2: 700 (Q47, V39)
MGMAT3: 700 (Q47, V39)
MGMAT tests are really good, and you can evaluate your 'fair score' by adding 2 marks to QA, while VA score is accurate. I knew 49/50 is my fair score for QA, while 38/39 is DOT accurate in VA. This was proved when I score the following scores in GMATPreps:
GMATPrep1: 750 (Q50, V40)
GMATPrep2: 740 (Q50, V39)
I realized that I was getting 50 in GMATPreps and 47/48 in MGMATs, whereas 38/39 in VA, same as GMAT Preps. I assumed that my faie score would be Q50, V38/39, i.e. a mid-point of 700 and 740, i.e. 720. This is when I thought there was no point waiting or study more. As a result, I booked an appointment for 17th August, 9.00am, at 9.00pm on 16th August. I think this is the right strategy, as I did not get any time to get tensed/overjoyed thinking about the test.
AWA was breeze, I think I will get a 6.0 again, QA went very, very, very smoothly. I finished the section in 50 minutes, i.e. 25 minutes before time. I did get tensed during English, but tried to maintain my calm, and forcibly maintained a strict, under 2-min/question time limit. I was not very confident after the VA section, and my heartbeat after the section would have been 100+. I kept praying to god, and finally saw a 720 !! 
Had I failed to perform in this test, I would have been unable to apply this year, and it would have been a big shock to me. But god did listen to me, and I got my ‘fair score’ , 1 day before I had originally scheduled the test !!