This paper discusses a discrete-time queueing system in which an arriving customer may adopt
four di erent strategies depending on the income information, two of them correspond to a
LCFS discipline where displacements or expulsions occur, and in the other two, the arriving
customer decides to follow a FCFS discipline or to become a negative customer eliminating
the customer in the server, if any. The di erent choices of the involved parameters make this
model to enjoy a great versatility, having several special cases of interest.