A method and apparatus for reducing call drop rate by validating reconfiguration messages based on service data unit (SDU) lifetime are described. A receiving device, such as a user equipment, may determine a receiving delay between receiving a first protocol data unit (PDU) and receiving a last PDU of a reconfiguration message SDU. The receiving delay may be compared with an SDU lifetime. The reconfiguration message SDU may be validated based on the comparison of the receiving delay with the SDU lifetime. A receiving delay that is greater than the SDU lifetime may indicate that the SDU is stale and, therefore, invalid. A receiving delay that is less than the SDU lifetime may indicate that the timing of the SDU is valid and the reconfiguration message SDU is to be processed. An activation time of the reconfiguration message SDU may also be honored or disregarded based on the receiving delay.