A method of operating a network node may be provided. A message may be sent from a first portion of the network node for configuring a time difference between an absolute time reference in the network node and a system frame offset for a served cell of the network node. An acknowledgement message from a second portion of the network node may acknowledge inclusion of the time difference in cell configuration data for the served cell. A further method of operating a network node may be provided. A message may be sent form the network node to a neighboring network node providing a time difference between a network time reference and a system frame offset for a cell in. An acknowledgement message may be received from the neighboring network node acknowledging inclusion of the time difference in cell configuration data for the served cell.