Your main DDI number is answered in PGM231 in a system message (VMIB 1). This message is recorded by the attendant as system message 001. This message (VMIB1) gives the caller 4 options set in PGM 228 (CCR). The 4 options in the CCR programming lets the cllaer press 1,2,3,4 to be transferred to different options/places, like a ring group with 3 phones. After 75 seconds as set in PGM191 under overflow timer the call will be routed to an overflow destination - also set in PGM191 for the ring group.
If you have different options in the menu function, you may be able to see, what the caller pressed in the menu, otherwise not.
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