See LI(22)P59017r1:
Discussion on the LI_T3 triggering interface for IMS in 3GPP SA3LI has uncovered a potential need for the ability to specify an H.238 Context Identifier as a target identifier. Since H.248 is not a 3GPP-specific protocol, this contribution proposes adding a target identity to TS 103 221-1 for this purpose.