Updated VS2015RC to RTM - Cordova Tools configuration for ios remote build agent is no longer valid. VS2015RTM cannot find taco-remote package installed on the remote mac (but VS2015RC could).
This is how it looks from the build remote agent command prompt (note 404 response not found):
Remote build server listening on [http] port 3000
ios-sim is installed on path at: /Users/admin/node-v0.12.4-darwin-x64/lib/node_modules/vs-mda-remote/node_modules/ios-sim/build/release/ios-sim
GET /modules/taco-remote 404 12ms
npm taco-remote --version outputs 2.10.1