Various communication systems may benefit from appropriate handling of reconfiguration. For example, certain wireless communication systems may benefit from lossless bearer reconfiguration when handling a transition from the user of a longer sequence number to a shorter sequence number. A method can include determining, by a protocol entity, if a next expected highest count value among count values associated with protocol data units received is more than a pre-defined limit ahead of a lowest count value among count values associated with protocol data units expected to be received. The method can also include resetting the next expected highest count value to a new value corresponding to a predefined upper limit, conditional on the determination.