with your present setup that means all, all pstn will go directly to
xxxxxx@au.voxalot.com as its your Default DP. if that's what you want to happen then thats the right way. just don't forget to put your desired "Ringing duration" in your voaxlot account "Voicemail Settings". find the right ringing duration until you achieve what you want.
my config suggestion earlier was for selective pstn call forwarding as i want "all" unaswered/busy calls goes directly to my vox vm and other selected pstn callers goes to another vm or can access my voip gateway (default DP) with pin.