Query regarding super built up.

I am buying a flat in Kolkata. The property is under construction and the possession will be given by June 2018. I have paid around 11 lacs to the developer and the rest I will be paying from ky home loan. The agreement for sale has been made in March 2016. The super built up area of the flat is 1091 sq ft and built up area is about 818 sq ft. The rate is 4500 per sq ft. I have heard that as per the new law the super built up has been removed. Can this be applicable in my case? Can I cancel the deal and will I get the refund of my 11 lacs ?