4.8.2.1 General

If the UE receives the indication that "interworking without N26 interface not supported" (see 3GPP TS 24.301 [15]), the UE operates as described in clause 4.8.2.2.

If the UE receives the indication that "interworking without N26 interface supported" and:

• the UE does not support dual-registration mode; or
• the UE supporting dual-registration mode determines to operate in single-registration mode,

the UE operates as described in clause 4.8.2.3.