Is is possible to override dns except when on specific network?

I have dns record for my domain correctly up, however I want to override it locally to go over vpn. So far I know what to do, dnsmasq can handle this. However, I want to override it to another ip address when I'm on specific network. And I don't know how to make this happen..

Basically I want to go over VPN except when I can go over LAN. Any advice?