My problem is, what will happen when i change the ip to my router, will my node reconnect over tor with the new vpn ip?
Depends on 1) where your node is located (network-wise) and 2) how the OS core runs on is configured.
Regarding 1):
Is your node inside your private network? If so, your node directly connects to your router (what else).
If your router is configured to use a VPN, the traffic from core will also be routed through VPN.
Regarding 2):
If you have a node outside of your private network and want to route everything through a VPN you have to use the VPN option of the OS.
This will lead to your node communicating via VPN.
If you clarify the topology of your network (and your setup you want to achieve) , we will be able to give you a more detailed answer.