We give the exact asymptotic of the tail of the stationary maximal dater in generalized Jackson networks with subexponential service times. This maximal dater, which is an analogue of the workload in an isolated queue, gives the time to clear all customers present at some time t when stopping all arrivals taking place later than t. We use the property that a large deviation of the maximal dater is caused by a single large service time in a single station at some distant time in the past of t and fluid limits of generalized Jackson networks to derive the asymptotic in question in closed form.