Provided also that in the case of selection for appointment by direct recruitment, with effect on and from the 1st April 1989, there shall be a ban on dereservation of vacancies reserved for the candidates belonging to any of the Scheduled Castes and Scheduled Tribes, Most Backward Classes and Denotified Communities to be appointed by direct recruitment. But, the above ban on dereservation of vacancies shall not be applicable to the vacancies reserved for the Backward Classes (other than Most Backward Classes and Denotified Communities), Backward Class Muslims and, therefore, if qualified and suitable candidates belonging to any of the Backward Classes (other than Most Backward Classes and Denotified Communities), Backward Class Muslims are not available for appointment, the turn so allotted to them shall lapse and the vacancy shall be filled by the next turn in the order of rotation. If sufficient number of qualified and suitable candidates belonging to any of the Scheduled Castes and Scheduled Tribes, Most Backward Classes and Denotified Communities are not available for selection for appointment for the vacancies reserved for them by direct recruitment in the first attempt of recruitment, then, a second attempt shall be made for selection of the candidates belonging to the respective communities by direct recruitment in the same recruitment year or as early as possible before the next direct recruitment for selection of candidates against such