The analysis of a preemptive priority queuing system with K(⩾ 2) classes of jobs is undertaken. The system consists of a single processor representing a model of discrete dynamic scheduling problems associated with Mk/Gk/1/∞ endogenous priority queues. The processor schedules jobs which arrive according to a Markov arrival process. The process of service is arbitrary. With each job are associated particular endogenous dynamic priorities, called scheduling by “mean bounded priorities with arrival pattern”. The main goal is, for the case of an arrival pattern of jobs, to present an original scheduling strategy, to derive the waiting time wk(t) and to discuss the implementation of the priorities. This queuing system is investigated.