(4)All refunds under this Section shall be made by the order of the Collector:Provided that if the stamp paper has been purchased before the provisions of this section come into force, no refund can be allowed or no instrument on such stamp paper can be executed after the expiry of one year from the date of its purchase as provided in sub-section (2) and sub-section (3) or after six months from the date of this Section coming into force, whichever is later."
