An apparatus of a Radio Access Network (RAN) node, a system, and a method. The apparatus includes one or more processors to generate a message including a downlink (DL) delivery data status (DDDS) frame including flags to indicate a presence of all associated optional information elements therein, the DDDS frame including information elements corresponding to an out-of-sequence delivery report for DL packet data convergence protocol (PDCP) protocol data units (PDUs) (PDCP PDUs) successfully delivered or delivered from the RAN node to a user equipment (UE); and cause transmission of the DDDS frame to a receiving node corresponding to the RAN node in a New Radio (NR) network, the receiving node hosting a NR packet data convergence protocol (PDCP) (NR PDCP) entity.