Question: Upon receiving an unexpected Floor Release message with acknowledgement required from the MCPTT floor participant, what action(s) does the floor participant interface toward the MCPTT client take based on local policy?
Option 1: Immediately forward the Floor Release message to the floor control server interface without any modification.
Option 2: Send a Floor Ack message to the MCPTT floor participant and modify the outgoing Floor Release message's subtype first bit to '0' (acknowledgement not required), then forward it to the floor control server interface.
Option 3: Wait for the Floor Ack from the floor control server before taking any further action with the received Floor Release message.
Option 4: Discard the Floor Release message since it was not expected and remain in the 'P: has no permission' state.
Explanation: When an unexpected Floor Release message with acknowledgement required is received, based on local policy, the interface may choose to acknowledge the message (by sending a Floor Ack) and then forward the modified message (with acknowledgement not required) to the floor control server. This ensures both acknowledgement of receipt and adherence to the message's forwarding requirements, highlighting the nuanced handling of messages in MCPTT interworking scenarios.