Yes, the behaviour has not changed.
Jan/31/2022 15:43:08 l2tp,debug,packet rcvd control message from CLIENT.IP.ADD:11701 to PUBLIC.IP.VPN.SEVER:1701
Jan/31/2022 15:43:08 l2tp,debug,packet tunnel-id=6631, session-id=1, ns=3, nr=2
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Message-Type=ICCN
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Framing-Type=0x1
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Tx-Connect-Speed-BPS=100000000
Jan/31/2022 15:43:08 l2tp,debug session 1 entering state: established
Jan/31/2022 15:43:08 l2tp,debug,packet sent control message (ack) to CLIENT.IP.ADD:11701 from PUBLIC.IP.VPN.SEVER:1701
Jan/31/2022 15:43:08 l2tp,debug,packet tunnel-id=1, session-id=0, ns=2, nr=4
Jan/31/2022 15:43:08 l2tp,debug,packet sent control message to CLIENT.IP.ADD:21701 from PUBLIC.IP.VPN.SEVER:1701
Jan/31/2022 15:43:08 l2tp,debug,packet tunnel-id=1, session-id=1, ns=2, nr=4
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Message-Type=CDN
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Result-Code=1
Jan/31/2022 15:43:08 l2tp,debug,packet (M) Assigned-Session-ID=1
Jan/31/2022 15:43:08 l2tp,debug session 1 entering state: stopping
It may be the 6.48.5, I can’t say, nor can I test right now on another version. So I’d recommend you to test that using a CHR with various versions before touching the actual server. I know there used to be an issue with this recently but I’ve thought it has been resolved before 6.48.5.