angular-cli: 6.0.0-rc.3 'ng update' does not work beyond the proxy due to 'Error: connect ECONNREFUSED 151.101.0.162:80'

Versions

Angular CLI: 6.0.0-rc.3
Node: 8.9.1
OS: win32 x64
Angular: 6.0.0-rc.3
... animations, cli, common, compiler, core, forms, http
... platform-browser, platform-browser-dynamic, router

@angular/cdk: 6.0.0-rc.2
@angular/compiler-cli: 5.2.9
@angular/flex-layout: 5.0.0-beta.13
@angular/language-service: 5.2.9
@angular/material: 6.0.0-rc.2
@angular-devkit/architect: 0.5.5
@angular-devkit/core: 0.5.5
@angular-devkit/schematics: 0.5.5
@ngtools/json-schema: 1.1.0
@schematics/angular: 0.5.5
@schematics/update: 0.5.5
typescript: 2.6.2
webpack: error

Repro steps

Upgrade the deps in the current project (including node_modules complete reinstall) run npm run ng -- update - this command need to be run to generate angular.json as per release notes https://github.com/angular/angular-cli/releases/tag/v6.0.0-rc.2

Observed behavior

Giving an error:

> ng "update"

events.js:183
      throw er; // Unhandled 'error' event
      ^

Error: connect ECONNREFUSED 151.101.0.162:80
    at Object._errnoException (util.js:1024:11)
    at _exceptionWithHostPort (util.js:1046:20)
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1182:14)