diff --git a/cli/internal/kubecmd/kubecmd.go b/cli/internal/kubecmd/kubecmd.go
index 4f9f84eded..0b93119b25 100644
--- a/cli/internal/kubecmd/kubecmd.go
+++ b/cli/internal/kubecmd/kubecmd.go
@@ -145,8 +145,14 @@ func (k *KubeCmd) UpgradeNodeVersion(ctx context.Context, conf *config.Config, f
 			err = compatibility.NewInvalidUpgradeError(nodeVersion.Spec.KubernetesClusterVersion,
 				string(conf.KubernetesVersion), innerErr)
 		} else {
-			versionConfig := versions.VersionConfigs[conf.KubernetesVersion]
-			components, err = k.updateK8s(&nodeVersion, versionConfig.ClusterVersion, versionConfig.KubernetesComponents, force)
+			versionConfig, ok := versions.VersionConfigs[conf.KubernetesVersion]
+			if !ok {
+				err = compatibility.NewInvalidUpgradeError(nodeVersion.Spec.KubernetesClusterVersion,
+					string(conf.KubernetesVersion), fmt.Errorf("no version config matching K8s %s", conf.KubernetesVersion))
+			} else {
+				components, err = k.prepareUpdateK8s(&nodeVersion, versionConfig.ClusterVersion,
+					versionConfig.KubernetesComponents, force)
+			}
 		}
 
 		switch {
@@ -161,7 +167,6 @@ func (k *KubeCmd) UpgradeNodeVersion(ctx context.Context, conf *config.Config, f
 			return fmt.Errorf("updating Kubernetes version: %w", err)
 		}
 	}
-
 	if len(upgradeErrs) == 2 {
 		return errors.Join(upgradeErrs...)
 	}
@@ -423,7 +428,7 @@ func (k *KubeCmd) isValidImageUpgrade(nodeVersion updatev1alpha1.NodeVersion, ne
 	return nil
 }
 
-func (k *KubeCmd) updateK8s(nodeVersion *updatev1alpha1.NodeVersion, newClusterVersion string, components components.Components, force bool) (*corev1.ConfigMap, error) {
+func (k *KubeCmd) prepareUpdateK8s(nodeVersion *updatev1alpha1.NodeVersion, newClusterVersion string, components components.Components, force bool) (*corev1.ConfigMap, error) {
 	configMap, err := internalk8s.ConstructK8sComponentsCM(components, newClusterVersion)
 	if err != nil {
 		return nil, fmt.Errorf("constructing k8s-components ConfigMap: %w", err)
diff --git a/cli/internal/kubecmd/kubecmd_test.go b/cli/internal/kubecmd/kubecmd_test.go
index fd8cb61ec0..9d1d37896b 100644
--- a/cli/internal/kubecmd/kubecmd_test.go
+++ b/cli/internal/kubecmd/kubecmd_test.go
@@ -444,7 +444,7 @@ func TestUpdateK8s(t *testing.T) {
 				},
 			}
 
-			_, err := upgrader.updateK8s(&nodeVersion, tc.newClusterVersion, components.Components{}, false)
+			_, err := upgrader.prepareUpdateK8s(&nodeVersion, tc.newClusterVersion, components.Components{}, false)
 
 			if tc.wantErr {
 				assert.Error(err)
diff --git a/internal/versions/versions.go b/internal/versions/versions.go
index d6ce41d0d1..c2a75bd3ae 100644
--- a/internal/versions/versions.go
+++ b/internal/versions/versions.go
@@ -85,7 +85,7 @@ func ResolveK8sPatchVersion(k8sVersion string) (string, error) {
 	if hasPatchVersion(k8sVersion) {
 		return k8sVersion, nil
 	}
-	extendedVersion := K8sVersionFromMajorMinor(k8sVersion)
+	extendedVersion := k8sVersionFromMajorMinor(k8sVersion)
 	if extendedVersion == "" {
 		return "", fmt.Errorf("Kubernetes version %s is not valid. Supported versions: %s",
 			strings.TrimPrefix(k8sVersion, "v"), supportedVersions())
@@ -94,10 +94,10 @@ func ResolveK8sPatchVersion(k8sVersion string) (string, error) {
 	return extendedVersion, nil
 }
 
-// K8sVersionFromMajorMinor takes a semver in format MAJOR.MINOR
+// k8sVersionFromMajorMinor takes a semver in format MAJOR.MINOR
 // and returns the version in format MAJOR.MINOR.PATCH with the
 // supported patch version as PATCH.
-func K8sVersionFromMajorMinor(version string) string {
+func k8sVersionFromMajorMinor(version string) string {
 	switch version {
 	case semver.MajorMinor(string(V1_26)):
 		return string(V1_26)