I am using 4 GV numbers for SP1-SP4 on an OBI202. I am using the SP1 number as my main dial in number for customers and trying to do rollover. Custom message AA is set up. I set up SP1 "forward on busy" to SP2 number and SP2 "forward on busy" to SP3 number. I have experimented by trying to make 3 calls to the OBI202 simultaneously. First call in gets AA with custom message. The caller dilas an extension and leaves a message. Second simultaneously call gets AA and dials an extension leaves a meassage. Third simultaneously call does not get AA instead it goes right to the GV voicemail for which is the SP3 GV number. I have set MAX sessions for each SP to 5. Also all phones (4) on the system are SPA508's Why can't I get AA to pick-up on the third simultaneously call?