Community Add-on: Network UPS Tools : how to shutdown my UPS

I cannot shutdown my UPS (directly connected via USB to my PI4 with HassOS):
I have setup “Network UPS Tools” add-on with the option “shutdown_host: true” (see below) but when the UPS changes its state to [LB OB], my RPI4 will nicely shutdown but the UPS itself is not shutdown (after the offdelay seconds, the parameter of the UPS): this means that if main power is recovered before UPS battery is completely exhausted, no power cycle will be applied to the RPI4 and it will never reboot…

Any ideas ?

YAML add-on conf:

devices:
  - config: []
    driver: usbhid-ups
    name: myups
    port: auto
mode: netserver
shutdown_host: true
users:
  - actions:
      - set
    instcmds:
      - all
    password: *****
    username: *****
log_level: info
list_usb_devices: true

I’ve been pondering this same problem. Haven’t solved it yet but thinking of putting a Sonoff S26 mains switch that’s been Tasmotised between the UPS and HA. Then having a totally separate ESP32 programmed to turn the switch off and on it it senses a power outage AND that HA is no longer running. So far I’ve got it to turn the switch and now working on the code to make sure it only does it when it has to. Tricky.

On the other hand I could just let the UPS run out (no graceful shutdown) and wait for the power to come back on. I’ve had enough power cuts to know it’s not done any harm in the past.