Depending on the trunks you have, the Mitel will still control the call until there is answer supervision.
So, if your call goes out a PRI, the Mitel knows it hasn't been answer and will recall it and send it to VM.
The timer that controls this is in the COS of the phone that was called.
Find the COS of the phone, edit it, go to the bottom of the page and scroll up until you find "Call forward no answer timer" and extend it out.
Ralph
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