neha988Firstly, GMAT score is not the only cut-off criteria, and that is true for all competitive MBA programs. They look at your profile holistically and shortlisting for interview is done based on various factors (GMAT, academics, past work-ex, essays, recommendations, diversity, etc).
I strongly recommend you apply in Round 2, even with a GMAT 680 (which, but the way, is a good score by any standard)
Reason I say so is that the chances of an admit and scholarships diminish progressively in subsequent rounds. More so for MBS, which puts great emphasis on class diversity, meaning there are restrictions on the number of students it accepts from any one region.
Also, another advantage of applying early is that if they really like the other aspects of your application but no so much your GMAT score, they are likely to put you on a Waitlist, which will give you an opportunity to improve your GMAT score.