A method of coordinating communications in a communication system, the communication system comprising an access node, communicatively coupled to: a first set of remote communication units (121, 122) being configured to operate in a full duplex, FDX, mode via respective ones of a first set of communication lines, and a second set of remote communication units (131, 132) being configured to operate in a Time Division Duplex, TDD, mode via respective ones of a second set of communication lines; wherein symbols transmitted on a first communication line connecting a first remote communication unit belonging to the first set of remote communication units (121, 122) to the access node have a first structure which comprises a first cyclic prefix portion, a data portion and a first cyclic suffix portion, and wherein a cyclic extension comprising the first cyclic prefix portion and the first cyclic suffix portion has a predetermined duration (t CE); and symbols transmitted on a second communication line connecting a second remote communication unit belonging to the second set of remote communication units (131, 132) to the access node have a second structure which comprises a second cyclic prefix portion and a data portion, the second cyclic prefix portion having the predetermined duration (t CE), and the symbol with the first structure and the symbol with the second structure having same symbol duration T symb; the method comprising: - transmitting by the first remote communication unit an upstream symbol with the first structure onto the first communication line at a reference time point t rf, wherein the reference time point t rf is determined based on a time of reception of a downstream symbol with the first structure t FDX_DS_RX and a first propagation delay over the first communication line t PD1, as t rf = t FDX_DS_RX - t PD1; - transmitting by the second remote communication unit an upstream symbol with the second structure onto the second communication line at t TDD_US_TX =t rf -t PD2 during a time interval assigned for upstream transmission on the second communication line, wherein t PD2 is a second propagation delay over the second communication line. a first set of remote communication units (121, 122) being configured to operate in a full duplex, FDX, mode via respective ones of a first set of communication lines, and a second set of remote communication units (131, 132) being configured to operate in a Time Division Duplex, TDD, mode via respective ones of a second set of communication lines; wherein symbols transmitted on a first communication line connecting a first remote communication unit belonging to the first set of remote communication units (121, 122) to the access node have a first structure which comprises a first cyclic prefix portion, a data portion and a first cyclic suffix portion, and wherein a cyclic extension comprising the first cyclic prefix portion and the first cyclic suffix portion has a predetermined duration (t CE); and symbols transmitted on a second communication line connecting a second remote communication unit belonging to the second set of remote communication units (131, 132) to the access node have a second structure which comprises a second cyclic prefix portion and a data portion, the second cyclic prefix portion having the predetermined duration (t CE), and the symbol with the first structure and the symbol with the second structure having same symbol duration T symb; the method comprising: - transmitting by the first remote communication unit an upstream symbol with the first structure onto the first communication line at a reference time point t rf, wherein the reference time point t rf is determined based on a time of reception of a downstream symbol with the first structure t FDX_DS_RX and a first propagation delay over the first communication line t PD1, as t rf = t FDX_DS_RX - t PD1; - transmitting by the second remote communication unit an upstream symbol with the second structure onto the second communication line at t TDD_US_TX =t rf -t PD2 during a time interval assigned for upstream transmission on the second communication line, wherein t PD2 is a second propagation delay over the second communication line. - transmitting by the first remote communication unit an upstream symbol with the first structure onto the first communication line at a reference time point t rf, wherein the reference time point t rf is determined based on a time of reception of a downstream symbol with the first structure t FDX_DS_RX and a first propagation delay over the first communication line t PD1, as t rf = t FDX_DS_RX - t PD1; - transmitting by the second remote communication unit an upstream symbol with the second structure onto the second communication line at t TDD_US_TX =t rf -t PD2 during a time interval assigned for upstream transmission on the second communication line, wherein t PD2 is a second propagation delay over the second communication line.