24.1 When an employee is required to assume the full responsibilities of a classification paying a higher rate, such employees shall be compensated at the higher rate for the period of that assignment, provided that the assignment is at least one (1) consecutive eight (8) hour work shift.

24.2 When a temporary vacancy occurs, it shall be filled by the employee receiving the highest ranking in accordance with the criteria chosen by the Employer for filling promotional vacancies. In the absence of up-to-date rankings, senior employees will be given preference.