per quintal Provided that the exemption under this notification shall not be admissible to a factory (a) which did not work during the base period, or (b) which had only a trial run in the base period, or (c) which commences production for the first time on or after the 1st day of October, 1972 : Provided further that in computing the production of sugar during the periods mentioned in column (2) of the said Table, (a) the data, as furnished in Form R.G. 1 prescribed in Appendix I to the Central Excise Rules, 1944, or in such other record as the Collector may prescribed under rule 53 or rule 173G of the said rules, shall be adopted : 765 (b) any sugar obtained from reprocessing of sugarhouse products left over in process at that end of the base period or earlier shall b e taken into account ; and (c) any sugar obtained by refining gur or Khandasari sugar, or any sugar obtained by reprocessing of defective or damaged sugar or brown sugar, if the same has already been included in the quantity of sugar produced, shall not be taken into account.