Interesting… I have big issues with IKEv2 behind NAT on both sides with actual 6.48.1, but still no news from MT. Was you able to run IKEv2 OK with this latest long term? Do you have your responder (server) behind nat on LTE connection? (see my other post http://forum.mikrotik.com/t/ipsec-ikev2-server-for-road-warriors-site-to-site-behind-double-nat-rb4011-and-os6-48-1/146761/21)