I was wondering if you can set an ADIX APS system to forward calls to VM if it is set to DND. Would I just have to have the person use call forwarding? They would like a call to go to VM right away when their phone is on DND.

I believe that it will do that by default if the phone is programmed ring/NA. Make sure that DND is allowed.

Depending on your software version, you can also reprogram the HOLD/DND button to HOLD/Quick Forward in key patterns.