A method for reconfiguring a timing relationship in a network, the network comprising at least three network nodes (113, 115, 119) each comprising a respective physical layer device, the physical layer devices pair-wise coupled between respective network nodes with a physical layer device of a first of each pair operating as a timing master and a physical layer device of a second of each pair operating as a timing slave, the method comprising operating in a first configuration of synchronous operation wherein a first of the network nodes provides timing for a second of the network nodes over the respective pair-wise coupling of physical layer devices, and the second of the network nodes operates in a feedthrough timing mode thus providing timing to a third of the network nodes over the respective pair-wise coupling of physical layer devices from the timing provided by the first network node, wherein the physical layer device of the second of the network nodes operates as a timing master and the physical layer device of the third network node acts as a timing slave, characterized by: detecting at the second network node that a data link between the first network node and the second network node has been dropped; transmitting from the physical layer device of the second network node to the physical layer device of the third network node using timing from a reference clock local to the second network node; in the event that the third network node was using a local reference clock recovered from the second network node, switching the local reference clock of the third network node to be responsive to an additional physical layer device of the third network node; freezing timing recovery in the receiver of the physical layer device of the third network node thereby locking the timing of the physical layer device of the third network node to the local reference clock of the third network; performing timing recovery in a receiver of the physical layer device of the second network node from a signal received from the physical layer device of the third network node; switching the physical layer device of the second network node to transmit using timing locked to a clock signal recovered by the receiver of the physical layer device of the second network node; and switching the physical layer device of the third network node to transmit using a clock signal responsive to the local reference clock of the third network node thereby operating in a configuration wherein the third network node provides timing for the second network node over the respective pair-wise coupling of physical layer devices. detecting at the second network node that a data link between the first network node and the second network node has been dropped; transmitting from the physical layer device of the second network node to the physical layer device of the third network node using timing from a reference clock local to the second network node; in the event that the third network node was using a local reference clock recovered from the second network node, switching the local reference clock of the third network node to be responsive to an additional physical layer device of the third network node; freezing timing recovery in the receiver of the physical layer device of the third network node thereby locking the timing of the physical layer device of the third network node to the local reference clock of the third network; performing timing recovery in a receiver of the physical layer device of the second network node from a signal received from the physical layer device of the third network node; switching the physical layer device of the second network node to transmit using timing locked to a clock signal recovered by the receiver of the physical layer device of the second network node; and switching the physical layer device of the third network node to transmit using a clock signal responsive to the local reference clock of the third network node thereby operating in a configuration wherein the third network node provides timing for the second network node over the respective pair-wise coupling of physical layer devices.