diff --git a/clitools/pkg/apis/monok8s/v1alpha1/osupgrade.go b/clitools/pkg/apis/monok8s/v1alpha1/osupgrade.go
index b6b4c98..f172804 100644
--- a/clitools/pkg/apis/monok8s/v1alpha1/osupgrade.go
+++ b/clitools/pkg/apis/monok8s/v1alpha1/osupgrade.go
@@ -18,11 +18,18 @@ const (
 	OSUpgradeProgressPhasePending     OSUpgradeProgressPhase = "pending"
 	OSUpgradeProgressPhaseDownloading OSUpgradeProgressPhase = "downloading"
 	OSUpgradeProgressPhaseWriting     OSUpgradeProgressPhase = "writing"
-	OSUpgradeProgressPhaseRebooting   OSUpgradeProgressPhase = "rebooting"
 	OSUpgradeProgressPhaseVerifying   OSUpgradeProgressPhase = "verifying"
 	OSUpgradeProgressPhaseCompleted   OSUpgradeProgressPhase = "completed"
 	OSUpgradeProgressPhaseFailed      OSUpgradeProgressPhase = "failed"
 	OSUpgradeProgressPhaseRejected    OSUpgradeProgressPhase = "rejected"
+
+	// Rebooting is the point-of-no-return phase.
+	//
+	// Once a node reaches Rebooting, the agent may have already changed the boot
+	// environment and requested a reboot. The controller must not supersede,
+	// retry, retarget, or otherwise mutate this progress object until the node
+	// comes back and the agent reports Completed or Failed.
+	OSUpgradeProgressPhaseRebooting OSUpgradeProgressPhase = "rebooting"
 )
 
 // +genclient
@@ -36,7 +43,10 @@ type OSUpgrade struct {
 	metav1.TypeMeta   `json:",inline" yaml:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty" yaml:"metadata,omitempty"`
 
-	Spec   OSUpgradeSpec    `json:"spec,omitempty" yaml:"spec,omitempty"`
+	// Specification of the desired behavior of the OSUpgrade.
+	Spec OSUpgradeSpec `json:"spec,omitempty" yaml:"spec,omitempty"`
+
+	// Most recently observed status of the OSUpgrade.
 	Status *OSUpgradeStatus `json:"status,omitempty" yaml:"status,omitempty"`
 }
 
@@ -91,7 +101,10 @@ type OSUpgradeProgress struct {
 	metav1.TypeMeta   `json:",inline" yaml:",inline"`
 	metav1.ObjectMeta `json:"metadata,omitempty" yaml:"metadata,omitempty"`
 
-	Spec   OSUpgradeProgressSpec    `json:"spec,omitempty" yaml:"spec,omitempty"`
+	// Specification of the desired behavior of the OSUpgradeProgress.
+	Spec OSUpgradeProgressSpec `json:"spec,omitempty" yaml:"spec,omitempty"`
+
+	// Most recently observed status of the OSUpgradeProgress.
 	Status *OSUpgradeProgressStatus `json:"status,omitempty" yaml:"status,omitempty"`
 }
 
diff --git a/clitools/pkg/controller/osupgrade/handler.go b/clitools/pkg/controller/osupgrade/handler.go
index 96322df..8680b88 100644
--- a/clitools/pkg/controller/osupgrade/handler.go
+++ b/clitools/pkg/controller/osupgrade/handler.go
@@ -258,7 +258,8 @@ func shouldProcessProgress(osup *monov1alpha1.OSUpgradeProgress) bool {
 
 	switch osup.Status.Phase {
 	case "",
-		monov1alpha1.OSUpgradeProgressPhasePending:
+		monov1alpha1.OSUpgradeProgressPhasePending,
+		monov1alpha1.OSUpgradeProgressPhaseRebooting:
 		return true
 	case monov1alpha1.OSUpgradeProgressPhaseFailed:
 		return osup.Spec.RetryNonce != osup.Status.ObservedRetryNonce