Chief Exam. In the event that the City provides a promotional exam for the position of Chief of Police and should the City extend the eligibility to participate in the promotional exam to Patrol Officers, a bargaining unit member must hold the position of patrol officer for two and one-half (2 1/2) years before he is eligible to test for Chief. Prior service credit with another employer does not satisfy the service requirement specified herein. Appointment to the Chief of Police shall be done in accordance with the City Charter. In the event that the City Charter is changed to include Patrol Officers then Patrol Officers may be eligible for appointment.