I did this once and I recall that installing unattended without network access… does not set the adapter to dhcp and sets it to a default of 192.168.1.1 because even after turning on the adapter and rebooting it wouldn’t take an address from the dhcp server on the subnet and would just keep 192.168.1.1.
Wasn’t an issue because I just set an ip once I turned the adapter on instead of diddling around changing the network subnet just to get to the gui.