Personal VPN routing

If you are using the normal netmask for a class C network (255.255.255.0), then the 192.168.1.x network is the same network, whether wired or wireless. If your server is on the 192.168.1.x, it's on the local network even if connects via wireless. You would need to sub-divide the network into two by extending the netmask by a bit. But, that will require re-addressing devices, setting up a router to route between the two networks, re-assigning IP addresses, gateway addresses, etc..

If you are in two facilities that each have a the default Class C network (you on wireless, your server on LAN), you need something in-between to act as a public route between the two networks. The 192.168.x.y is reserved for local use, and there can be a multitude of these networks geographically dispersed, that connect through the internet via NAT re-addressing.

What I am hoping to do is that if I'm on a class C network via wifi and I want to contact a Class C address that is in the same 255.255.255.0 mask on another Class C network via the VPN. So basically I was hoping there was a way in the Personal VPN that I could add a route that says "if address is 192.168.1.40" then route it down the VPN... and let everything else on that Class C address family route locally. I doubt this is possible, but I get lost in the VPN parameters and controls at times. I wonder if my solution isn't to force the traffic over cellular if the server is not on the local address... I've watched the developer videos from WWDC but not clear how I can force my traffic to use the cellular connection over the wifi for the traffic I want to send down the tunnel to the remote local network for just our app.