This happens because it expects an extra newOptions argument before the callbacks, which is neither documented nor provided by the variation functions calling it. So the successCallback is received as newOptions and errorCallback is received as successCallback.
The result is that on success, the errorCallback is invoked and on error no callback is invoked.
This happens because it expects an extra newOptions argument before the callbacks, which is neither documented nor provided by the variation functions calling it. So the successCallback is received as newOptions and errorCallback is received as successCallback. The result is that on success, the errorCallback is invoked and on error no callback is invoked.