le shutdown with net

service shutdown_with_net.service:

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[Unit]
Description=System shutdown script with network
After=network.target
Wants=network.target

[Service]
Type=oneshot
Environment=HOME=/storage
ExecStart=/bin/true
ExecStop=-/bin/sh -c ". /etc/profile; exec /bin/sh /storage/.config/shutdown_with_net.sh"
RemainAfterExit=yes
KillMode=none
SendSIGKILL=no
TimeoutSec=5min
TimeoutStopSec=5min

[Install]
WantedBy=multi-user.target
----------------------------------------------------------------

install and enable service:
cp shutdown_with_net.service /storage/.config/system.d/
systemctl enable shutdown_with_net.service

for testing I used
file autostart.sh:
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echo "" >>/storage/ping
echo -n "autostart      " >>/storage/ping
date "+%H:%M:%S" >>/storage/ping

(
  sleep 20
  reboot
)&
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and file shutdown_with_net.sh:
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echo -n "shutdown start " >>/storage/ping
date "+%H:%M:%S" >>/storage/ping
sync

ping -c 20 -q 10.0.0.1

echo -n "shutdown done  " >>/storage/ping
date "+%H:%M:%S" >>/storage/ping
sync

----------------------------------------------------------------

result:
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autostart      14:17:47
shutdown start 14:18:05
shutdown done  14:18:24

autostart      14:18:38
shutdown start 14:18:57
shutdown done  14:19:16

.......................
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