DND Behavior (Busy vs Unavailable)

I have a question that was asked a few years ago here

Is there a way to change the behavior of the DND on the phone (Aastra 6867i) so that the “unavailable” is played instead of the “busy” message ?

I’ve tried to use the feature code *76 instead of the DND key on the phone but it’s the same thing for both situations.

Thank you

This may not be the best solution but it is one I have used before, if the Aastra phones aren’t able to provide the unavailable command then this may be an option.
At the bottom of the extensions page in the voicemail section the three boxes say something like:
“unavailable message if enabled”
“busy message if enabled”
“unavailable message if enabled”

You can change the middle destination to voicemail>same extension number (unavailable message)

Now this will always play the unavailable message, even if you reject an incoming call, which may not be what you want.

Thanks for the idea, at least it gives me an alternative of nothing else works.