Where any goods sent on approval basis, not earlier than six months before the appointed day, are rejected or not approved by the buyer and returned to the seller on or after the appointed day, no tax shall be payable thereon if such goods are returned within six months from the appointed day:

 

PROVIDED that the aforesaid period of six months may, on sufficient cause being shown, be extended by the competent authority for a further period not exceeding two months:

 

PROVIDED FURTHER that the tax shall be payable by the person returning the goods if such goods are liable to tax under this Act, and are returned after a period of six months or the extended period, as the case may be, from the appointed day: