A timing adjustment method for use in a multi-hop communication system is provided. The method includes transmitting information in a first labelled interval from a first apparatus along a plurality of consecutive links of a path via one or more intermediate apparatuses to a second apparatus, said information including a reference to a particular one of said labelled intervals and the transmission of that information incurring a delay such that the transmitted information, or information derived therefrom, is received by said second apparatus in a second labelled interval a number of such intervals after the first labelled interval. The method also includes adjusting said reference to form an adjusted reference referring to a further labelled interval the or another number of such intervals before or after the particular labelled interval.