How to execute a logon script after VPN connects

I have been fighting how to add static routes to a VPN connection automatically.  I finally found the answer by motifying the script from the solution here https://www.experts-exchange.com/questions/22594402/Add-a-default-route-to-VPN-connection.html?anchorAnswerId=19160532#a19160532

Now I am wondering if there is anyway to make the script execute automatically after connecting and not be a login script.