Where the full amount of any grant paid under this Act in respect of any premises, or an amount not less than that repayable under section 14(3) or which would have been so repayable if, at the time of the repayment, there had been a breach or contravention of a condition, has been repaid to the Ministry, the observance of the conditions imposed under this Act with respect to those premises shall, if the Ministry so directs in writing, cease to be required notwithstanding that the period for which those conditions were imposed has not expired.