I'm a tenant in 6-apartment rent-stabilized building in NYC. I lived in the building 20 years and since it's a 1st floor apartment was using the backyard sporadically as i have a metal staircase (not fire escape) that accesses the backyard. Recently the building got sold and the new owner is taking over one of the empty apartment for his usage. Can he forbid me from using the backyard even though nothing in the lease says about usage or lack of access to the yard?