802.11s mesh two wan

i have initially create a 802.11s mesh following the wiki.
Now the network topology looks like:

All 3 groups of pc are in different zone...The mesh master act as DHCP, gateway and DNS...

Now i have the possibility to add another external wan on

Is possible to route the "zone 3" clients through the new wan (and maintain the mash capabilities, for DNS, DHCP and lan/802.11r comunication)?
The other zone (1 & 2) will continue to use WAN 1.
there a simpe solution? :slight_smile: