This disclosure provides a network node, and a method of operating the network node, having one or more communications interfaces connectable to a first communications network and to a second communications network, the method including the network node accessing a service using the first communications network; analyzing data relating to the first communications network to identify a plurality of fault-indicative events; determining a rate of the plurality of fault-indicative events per unit time; and the network node accessing the service using the second communications network in response to a first trigger, wherein the first trigger is based on the rate of the plurality of fault-indicative events per unit time.