Construction under Declaration Suite

Hello We purchased a property along with our neighbour. We are entitled for 180 sq. yards and other side is for 100 Sq. yards. There is Stair case in between both the properties which comes under our 180 sq. yards . We thought after purchasing the House , we will demolish the stair case and built a wall protecting our property . So in Sale deed blue print stair case land is shown plain..This Change the mind of neighbour to acquire that 10 sq. yards ( Stair Case) . We filed injunction suite which dismissed for not proving the evidence of Stair case..Commissioner Appointment was also done under this suite , but did not get ticked in court in valid time . So That also gone in Vain. Then we filed Appeal (AS ) ,which dismissed for default .,Now already 15 years passed for this small issue..I am planning for Declaration suite that We are the owner of 180 sq. Yards along with Stair Case..So is it possible to construct 170 sq. yards or less during declaration suite case going on in court ? ?..Please suggest good Advice