Confused about the approach for my GMAT retake!! Guidance required!!

Hi,
I begin with apologising for a long post, but I am really stressed right now!!

I am a non-native english speaker from India and I aspire to be in the top 20 business schools and have been putting quite a lot of efforts into preparing for my GMAT. I have depended on self study right through my preparations.

2015:
I took my first GMAT in March 2015 and scored a 600 (Q47, V25) and I must admit that my level of preparation was really low (2 weeks) and had not taken practice tests until a few days before the exam (I thought I want to save it till the end!) I scored 580 and 590 in both the tests and the result on D-Day was similar. I almost forgot about GMAT and got busy with my busy consulting job chasing promotions, etc

2016:
This year, since July, I committed myself to regular self study for the past couple of months. Completed OG16 and the verbal OG16 and used to practice 20 question timed at one go and had accuracy of over 90-95% in the first 50% question and over 85% in the last few which are considered tougher. I wanted to recalibrate my score by taking the GMATPrep tests, so I reset my free tests and I scored 680 and 690 with Quant49-50 and verbal35-32. I did observe some repeated questions and RC passages though it was taken over a year ago. My target was to score a psychological 700+.

This week:
With an intent of taking the GMAT exam the moment I cross 700, I took week off this week and took two more paid GMAT exam pack tests and tons of practice and my confidence is now shattered. I scored 610 3 days ago and 570 today(Q45, V23). I am not sure what is going wrong and cannot explain the drop in scores. Or maybe my level never improved and the 680s were an outlier because some questions repeated. My timing was okay and did not leave any questions till the end. Plenty of silly mistakes, and got easy questions wrong. I'm not much worried about my Quant as I usually have 95%+ accuracy in PS and 90%+ in DS in OG questions in a timed environment. What worries me is verbal. I've gone through at least 2000+ verbal questions with decent accuracy and understanding from various sources including Manhattan, Veritas and Kaplan. I'm probably made a wrong approach my default approach!!


What should I do?
I really wanted to take GMAT at the earliest as R1s of admissions are about to start. I cant wait another year, I have 6 years exp already and most of it is international. My job demands travel of over 80% and I'm in a different country every 4-6 months. My score in GMAT does not reflects neither the job profile I hold, nor the undergrad accomplishments. I am into business strategy consulting(3 promotions in 5 years) inspite of being the only engineer amongst B-School grads, with a bachelors degree from one of the top IITs(6.4/10). I really need a good GMAT score to compensate for my average grades in undergrad. I am quite confident about my work ex and other aspects of the application with loads of ECA, but GMAT is letting me down.

I can't take classroom coaching due to travel. I'll be in Philippines(plus many other countries) till end of this year, so time zones keep changing to even register for live classes. I have to unlearn many of my self developed strategies. Self study is clearly not working!! I need help!! What should be my approach? I will really appreciate any advice from you all. Thanks a lot!!

Best Regards,
Manj