Question: In a UTRAN to GSM cell handover scenario for a combined TDD (7.68 Mcps option) and GSM UE, what marks the starting point for measuring the handover delay?
Option 1: Transmission of the first message on the new RAT channel
Option 2: End of the last containing an "RRC Connection Release" message implying hard handover
Option 3: Initiation of the handover procedure by the UE
Option 4: Receipt of the "Handover Command" by the UE
Explanation: The correct starting point for measuring the UTRAN to GSM cell handover delay is the end of the last message that implies a hard handover, which in this context is specified as the "end of the last containing an message implying hard handover". This marks the transition from the old RAT to the new one, and thus, the beginning of the handover delay measurement. Option 2 accurately reflects this definition.