netplan setup is one time and may not even be needed

roles/network/tasks/install.yml

@@ -45,6 +45,8 @@
 #     dest: /etc/network/if-pre-up.d/iptables
 #     mode: '0755'
 
+- name: avahi
+  include_tasks: avahi.yml
 
 # Ongoing rework (e.g. PR #2652) arising from ansible.posix collection changes:
 - name: "4 network settings in /etc/sysctl.conf -- e.g. disabling IPv6 (this might be overkill, as IPv6 should really only be disabled on the LAN side, i.e. br0)"
@@ -76,6 +78,11 @@
   include_tasks: roles/network/tasks/squid.yml
   when: squid_install and squid_installed is undefined
 
+  #preprep for backends
+- name: Netplan in use on Ubuntu 18.04+
+  include_tasks: netplan.yml
+  when: is_ubuntu
+
 # all installs
 - name: Install /usr/bin/iiab-internet-on|off from template (root:root by default)
   template:
@@ -88,9 +95,6 @@
     - gateway/iiab-internet-on
     - gateway/iiab-internet-off
 
-- name: avahi
-  include_tasks: avahi.yml
-
 # mate desktop detection based on 'register: nd_dir' in enable_services
 - name: Check if /usr/share/mate/autostart/ exists
   stat:

roles/network/tasks/main.yml

@@ -59,11 +59,6 @@
 #    include_tasks: squid.yml
 #    when: squid_install and FQDN_changed and iiab_stage|int == 9
 
-  #preprep for backends
-  - name: Netplan in use on Ubuntu 18.04+
-    include_tasks: netplan.yml
-    when: is_ubuntu and not is_ubuntu_16
-
   #### Start services
   - name: hostapd
     include_tasks: hostapd.yml