The valuation officer may at any time cause to be made in a valuation list any alteration which is necessary to correct any clerical or arithmetical error therein and the list shall have effect accordingly, but if the alteration is made in respect of any matter other than totals," the officer shall, before r causing the alteration to be made, send notice thereof to the occupier of the hereditament affected and to the rating authority of the rating area, and shall allow fourteen days to elapse during which any person concerned may object to the proposed alteration.