Policy route if VPN down

Hi all, I'm forwarding all my branch office traffic to an IPSec VPN with my HeadQuarter office (for security reason). If the VPN is down, i'm losing management access to my Fortigate and all users can't access Internet anymore.

I tried two identical 0.0.0.0/0.0.0.0 static routes with same distance / different priority but than didn't work (all trafic still went to the default wan interface, even with an "execute router restart").

So I finally use two identical Policy-route where only the Outgoing interface is different : one goes to the VPN tunnel (position #1), the other one forward trafic to the WAN interface (position #2). While it's working currently, I'm not sure how the Fortigate will behave if my tunnel goes down. When there's a policy match, if the gateway / interface is down, is the policy ignored for the next one ? If not, how can I configure everything properly ? Thanks