Section 412A(iii) in Kolkata Municipal Corporation Act, 1980
(iii)simultaneously with the making of the declaration under clause (ii), the Corporation will serve a notice upon the owner or owners, as the case may be, and paste it on the outdoor of the building providing an option to the owner or owners, as the case may be, of the building to reconstruct the building according to the plan to be sanctioned by the Corporation with such expedition as possible and providing for maximum floor area necessary for accommodating the erstwhile occupier or occupiers, as the case may be, and additional floors as may be required for recovery of the expenses for construction after relaxation of the applicable building rules. In the event, the owner or owners as the case may be, so agreeing and applying, the Corporation shall allow a building plan submitted for the purpose to be sanctioned with additional floors and floor areas so as to provide for the recovery of the expenses to be incurred;