Upgrade kubernetes from rancher

In 1.1.0 I see the ability to upgrade version of kubernetes from rancher. But I cannot find how to do that. Please help.
Currently I running k8s 1.2.4 and want 1.3.0

K8s 1.3 will be available in Rancher 1.2.0-pre1 shortly. (It will not be available in 1.1.x)

So I need to upgrade Rancher before upgrading k8s? And this is true for any future updates of k8s?

In this case yes; Future versions will depend on what changed, if it requires Rancher/Cattle changes, and the degree of those changes. Generally 1.x.y patch releases probably won’t, and 1.z.0 releases probably will.