1The working licence shall remain in force until the expiration of six months from the date of withdrawal and no longer.
2Where any rent payable under the working licence (or any sum to be allowed in account in lieu of rent thereunder) is to be calculated or adjusted by reference to the rent to be reserved by the freeholder's lease the application for Which is withdrawn, the rent so reserved shall for that purpose be taken to be the aggregate of the following—
(a)a rent payable on the amount of coal worked under the licence—
(i)in a case where the coal was being worked by the proprietor in the financial year ending the thirty-first day of March, nineteen hundred and forty-two, at the same rate as was assumed for the purpose of assessing mineral rights duty on him in that year; or
(ii)in any other case, at such rate as may be determined by arbitration to be the rate which would have been so assumed if the coal had been so worked; and
(b)a rent payable on the amount of any minerals carried away through any mine to which the licence relates (other than coal worked under the licence) at such rate as may be determined by arbitration to be just.
3Any provision in the working licence that a rent or sum to be calculated or adjusted as aforesaid shall not be paid or allowed in account until the granting of a freeholder's lease shall not have effect.
4The working licence shall be deemed to have been granted subject to the condition that the licensee shall—
(a)exercise in relation to the premises to which the licence relates such care as is exercised under the ordinary practice of the management of mineral estates by prudent owners in relation to property that is to continue in their ownership ; and
(b)deliver up those premises to the Commission in the same state (except for things properly done under the licence) as they were in on the vesting date.