Auto-Assign IPs will automatically be assigned if:
- You have a managed route assigned to the network.
- You have an auto assign range that falls within the managed route.
- It does not already have an address assigned that falls within the managed route.
In your case, your managed route is 192.168.0.0/16 and you manually assigned it to 192.168.0.1. That address falls within 192.168.0.0/16, and as such, no additional addresses will be assigned.
If your managed route was 192.168.1.0/24 (matching your auto assign range), then an additional address within 192.168.1.0/24 will be assigned even when manually assigning addresses outside of that range unless “Do Not Auto-Assign” is checked for the node.