Various example embodiments are disclosed herein. A technique is provided for detecting, by a secondary base station (BS), a trigger condition in a wireless network, the wireless network including a mobile station (MS) that is connected to both a master base station (master BS) and a secondary base station (secondary BS), and sending a protocol data unit (PDU) status report from the secondary BS to the master BS in response to the secondary BS detecting the trigger condition, the PDU status report identifying one or more PDUs or portions thereof for further transmission to the MS.