Embodiments herein relate to a method performed in a wireless terminal (10) for managing or handling uplink, UL, data transmissions in a radio communications network (1), wherein the wireless terminal (10) is served by a first radio base station (12) and a second radio base station (13) providing dual connectivity to the wireless terminal (10) in the radio communications network (1). The wireless terminal (10) transmits a buffer status report, BSR, to the first and/or second radio base station when a trigger is being fulfilled as configured at the wireless terminal (10). Furthermore, the wireless terminal (10) handles multiplexing of an uplink data transmission towards the first and second radio base stations according to a static configuration defining how to multiplex Media Access Control Service Data Units, MAC SDUs, from one or different logical channels onto transport blocks to be delivered to a physical layer on transport channels of a given radio base station out of the first radio base station and the second radio base station; and/or according to a second configuration where if there is data available for multiple logical channels with equal priority towards one of the radio base stations, then data of a logical channel for which the buffer status report is configured towards a radio base station providing a grant, is prioritized.