The method used to determine the local IP address involved having access to the Google DNS (8.8.8.8).
The code has been modified so that is no longer the case.
The updated code will allow successful IP address discovery even if there is no connection to the Internet.
Connection to the local router is still required, but the router does not need to be connected to the Internet.
You can now use an access point to provide the local IP address for standalone operations.