How to force dhcp reload if WAN gateway is down

[meepmeep]

I replaced my ISP box a long time ago with an opnsense, and everything works perfectly, until the ISP makes some interventions on my line and interrupts my connection.

Each time it's the same problem: the gateway is marked as "down" on the dashboard, but on "Interface -> Overview -> WAN" side the status and DHCP are UP.
So opnsense doesn't bother to do a release/reload of the WAN dhcp lease ... and I'm offline until I do a manual intervention on WAN interface (reload/release or a full reboot)

I've gone through all the possible options several times, and I don't see where to tell opnsense "if the WAN gateway is down, do a reload/release until it's up!"

Is it possible ?

[meepmeep]

It looks like a good old "ping external address" on cron is the perfect solution :
https://forum.opnsense.org/index.php?topic=11928.0
https://forum.opnsense.org/index.php?topic=18300.0