Changing approved plan

[krishnakumar]

Hi
I am constructing a duplex house in a 30x40 plot which comes under bbmp road width 9.~ mtrs. I had got plan approval for stilt+3 floors with a plan to construct 3rd floor later. Now I feel I can only afford a small house in the ground floor and rest for parking and 3rd floor I may not be able to construct. I should have thought about it during approval but the other plan looked better at that time. In order to make these changes should I get my approved plan modified and approved again or since I am anyway not building the 3rd floor can i go ahead and build the ground floor part?

Thanks
Krishna