If a worker has been receiving a shift differential or some other differential or pay for work-out-of‑class as provided in this MOU or in the Salary Ordinance for 30 or more calendar days immediately preceding a paid holiday, or the commencement of a vacation or the commencement of a paid sick leave period, or compensatory time off, as the case may be, the applicable differential shall be included in such worker’s holiday pay, vacation pay, paid sick leave or paid compensatory time. The vacation, sick leave, holiday and compensatory time off pay of a worker on a rotating shift shall include the shift differential such worker would have received had they been working during such period.