(a) Where on promotion or transfer, a member of a class of a service in a division, category, or grade is holding an appointment in another division, category or grade thereof or in another class of service, no penalty shall be imposed upon him in respect of his work and conduct before such promotion or transfer except by an authority competent to impose the penalty upon a member of the class of service in the latter division, category or grade or class of service, as the case may be.
(b) Where a person has been reverted or reduced from one class of service to another, or from one division, category or grade of a class of service to another division, category or grade thereof, no penalty shall be imposed upon him in respect of his work and conduct while he was a member of the class of service, division, category or grade, as the case may be from which he was reverted or reduced except by any authority competent to impose the penalty upon a member of such class of service, division, category or grade, as the case may be.