The shortlisting of regular candidates for admission into M.Tech. Programmes will be based on GATE score only. The fixing of cut-off score for candidates in different categories shall be as per the norms of the Institute.However no cur offs are announced yet.
I think they will fix it based on the number of applicant. If you are interested in applying for IIT BBS, you can apply online. Its application are open till 3rd Apr 2016
Selection of regular candidates is based on 70% weightage for the GATE score and 30% weightage for the performance in the Written Test and Interview.