From pr builder:
http://kubekins.dls.corp.google.com:8081/job/kubernetes-pull-build-test-e2e-gce/19314/testReport/junit/(root)/Kubernetes%20e2e%20suite/Services_should_be_able_to_change_the_type_and_nodeport_settings_of_a_service/

Most likely because https://github.com/kubernetes/kubernetes/blob/master/test/e2e/service.go#L512. So just loop around till we hit a free port?