A method performed by a first unit of a base station system of a wireless communication network, for handling user plane data streams for transmission over fronthaul links between the first unit and a second unit of the base station system, the base station system comprising a baseband unit and a radio unit, the radio unit being arranged to transmit the user plane data streams wirelessly to, and receive from, one or more wireless communication devices, wherein the first unit is the baseband unit and the second unit is the radio unit, or wherein the first unit is the radio unit and the second unit is the baseband unit, the method comprising: transmitting a first user plane data stream to the second unit over a first fronthaul link, the first user plane data stream being encoded with a first encoding scheme resulting in a first data rate; transmitting a second user plane data stream to the second unit over at least one second fronthaul link, the second user plane data stream being encoded with a second encoding scheme resulting in a second data rate; obtaining information of a link failure of the first fronthaul link, and in response to the obtained information of the link failure, and when the first and the second user plane data streams do not fit into the at least one second fronthaul link encoded with the first and the second encoding scheme, respectively, characterized by transmitting, to the second unit over first communication resources of the at least one second fronthaul link, the first user plane data stream encoded with a third encoding scheme resulting in a third data rate, and transmitting, to the second unit over second communication resources of the at least one second fronthaul link, the second user plane data stream encoded with a fourth encoding scheme resulting in a fourth data rate, wherein at least one of the third data rate is lower than the first data rate, and the fourth data rate is lower than the second data rate. transmitting a first user plane data stream to the second unit over a first fronthaul link, the first user plane data stream being encoded with a first encoding scheme resulting in a first data rate; transmitting a second user plane data stream to the second unit over at least one second fronthaul link, the second user plane data stream being encoded with a second encoding scheme resulting in a second data rate; obtaining information of a link failure of the first fronthaul link, and in response to the obtained information of the link failure, and when the first and the second user plane data streams do not fit into the at least one second fronthaul link encoded with the first and the second encoding scheme, respectively, characterized by transmitting, to the second unit over first communication resources of the at least one second fronthaul link, the first user plane data stream encoded with a third encoding scheme resulting in a third data rate, and transmitting, to the second unit over second communication resources of the at least one second fronthaul link, the second user plane data stream encoded with a fourth encoding scheme resulting in a fourth data rate, wherein at least one of the third data rate is lower than the first data rate, and the fourth data rate is lower than the second data rate.