Advertise Default Route Contingent on WAN Interface Up

I have a Max BR1 mini that uses WiFi to connect to a remote network. The BR1 BGP peers to another Max BR1 and advertises a default route through BGP. Is there a way to make the route advertisement in BGP dependent on the WAN WiFi network being up?

Currently the only way for me to remove the route advertisement is to disable the BGP session on the BR1.