15. Effect of change of occupier---Where a notice or crossnotice is
 duly given by the occupier of any land to the occupier of any other land
 in accordance with this Act, but, before the matter is settled (whether
 by agreement or order of the Court), one of the parties disposes of his
 interest in either of the parcels of land concerned, the notice or
 crossnotice shall cease to have effect.