You can use the following code:
add_action( 'request', function( $request ){
if( empty( $request ) ){
wp_safe_redirect( get_home_url() . '/lunchtime-results/' );
exit;
}
return $request;
});
This can be added to your theme’s functions.php file.
The code checks the current request arguments. When visiting the home page the request is empty; in all other cases it would include some arguments.
So if the request is empty (is home page) it redirects to a new URL setting the HTTP status to 302(Found).