Job work transitional relief: tax exemption where inputs are returned within the prescribed period, subject to declaration and recovery. Transitional relief exempts tax on inputs or goods sent to job workers or other premises before the appointed day if returned to the original place of business within the prescribed transitional period; the Commissioner may permit a limited extension for sufficient cause, failure to comply leads to recovery of input tax credit under the referenced recovery provision, and the exemption is conditional on prescribed declarations by the consignor and the job worker of goods held on the appointed day.