Question: In a Voice Group Call Service (VGCS) scenario where 'group call re-establishment by the BSS' is supported by both the MSC and BSC, and a cell's group call channel needs to be released due to equipment failure, how does the BSS inform the MSC if the channel was serving the current talker?
Option 1: With a Clear Request message
Option 2: With an Uplink Release Indication and VGCS Assignment Status message
Option 3: By initiating immediate clearing of both radio and terrestrial resources
Option 4: Through a dedicated link release notification for the talker
Explanation: When 'group call re-establishment by the BSS' is supported, to maintain group call continuity, detailed information about the channel's status at the time of failure is crucial. If the group call channel was serving the current talker, the BSS uses a combination of messages (Uplink Release Indication and VGCS Assignment Status) to inform the MSC about the failure, ensuring the MSC retains terrestrial resources for potential re-establishment, without immediately clearing them, facilitating quicker recovery once the issue is resolved, minimizing service disruption.