Debian Linux dgrp_cfg_node, there can be only one

Debian Buster

I’m only able to spring the following tty into existence:
sudo dgrp_cfg_node -v -p 771 -e never -g dialout init ZA 192.168.13.11 1

If I try to create the following:
sudo dgrp_cfg_node -v -p 772 -e never -g dialout init ZB 192.168.13.12 1

it doesn’t work. I have swapped Digi One SPs around, reconfigured them in a variety of ways. Tried them in different locations. The only tty I can get is ttyZA00. I see the line for ZB in /etc/dgrp.backing.store , but it never shows in /dev.

Here is what I have in 10-dgrp.rules
/etc/udev/rules.d/10-dgrp.rules
#KERNEL==“tty_dgrp*”, PROGRAM=“/usr/bin/dgrp_udev %k”, SYMLINK+=“%c”, TAG=“systemd”
KERNEL==“tty_dgrp*”, PROGRAM=“/usr/bin/dgrp_udev %k”,SYMLINK+=“%c”, NAME=“%c”, GROUP=“dialout”,MODE=“0660”,OPTIONS=“last_rule”

I’m in a field in a remote location and have currently run out of ideas. Open to any ideas. FWIW I’ve been successfully doing what I’m trying to do for several years. Never have run into this before. I have several machines running multiple Digis without issue. Been banging my head on this one for a few hours now.

Problem was (mostly) between the keyboard and chair. Because I was setting up local with 192.168 addresses, I shouldn’t have been using port 772. I port forward 772 in the modem to local IP and 771. There was still something I don’t understand, but I got it working so I’m moving on.