Question: What happens when the value of the Fixed Point to Billing Identifier (FPBI) is changed for a given Charging Triggering System - Fixed Point (CTS-FP)?
Option 1: The change is silently updated across all enrolled Charging Triggering System - Mobile Stations (CTS-MS).
Option 2: Each enrolled CTS-MS needs to be enrolled again, effectively triggering a CTS-FP re-initialisation.
Option 3: The FPBI change only affects new CTS-MS enrollments, while existing ones remain unaffected.
Option 4: The system automatically assigns a new unique FPBI to prevent conflicts.
Explanation: Changing the FPBI value for a given CTS-FP is considered a re-initialisation of that CTS-FP. As a result, every CTS-MS that was previously enrolled needs to undergo the enrollment process again to ensure seamless and accurate billing and charging operations.