diff --git a/controller/controller.go b/controller/controller.go
index 945f80b347..25fa6c0c77 100644
--- a/controller/controller.go
+++ b/controller/controller.go
@@ -252,9 +252,9 @@ func NewManager(
 	return cm
 }
 
-// Run will sync informer caches and start controllers. It will block until stopCh
-// is closed, at which point it will shutdown the workqueue and wait for
-// controllers to finish processing their current work items.
+// Run will set up the event handlers for types we are interested in, as well
+// as syncing informer caches and starting workers. It will block until stopCh
+// workers to finish processing their current work items.
 func (c *Manager) Run(rolloutThreadiness, serviceThreadiness, ingressThreadiness, experimentThreadiness, analysisThreadiness int, stopCh <-chan struct{}) error {
 	defer runtime.HandleCrash()
 	defer c.serviceWorkqueue.ShutDown()
diff --git a/manifests/crds/rollout-crd.yaml b/manifests/crds/rollout-crd.yaml
index bceef3edf5..4ca6f2308d 100644
--- a/manifests/crds/rollout-crd.yaml
+++ b/manifests/crds/rollout-crd.yaml
@@ -64,6 +64,8 @@ spec:
               revisionHistoryLimit:
                 format: int32
                 type: integer
+              scaleDownOnAbort:
+                type: boolean
               selector:
                 properties:
                   matchExpressions:
diff --git a/manifests/install.yaml b/manifests/install.yaml
index 3eb0ed9241..21617077d1 100644
--- a/manifests/install.yaml
+++ b/manifests/install.yaml
@@ -9753,6 +9753,8 @@ spec:
               revisionHistoryLimit:
                 format: int32
                 type: integer
+              scaleDownOnAbort:
+                type: boolean
               selector:
                 properties:
                   matchExpressions:
diff --git a/manifests/namespace-install.yaml b/manifests/namespace-install.yaml
index e287817f07..eec18188cd 100644
--- a/manifests/namespace-install.yaml
+++ b/manifests/namespace-install.yaml
@@ -9753,6 +9753,8 @@ spec:
               revisionHistoryLimit:
                 format: int32
                 type: integer
+              scaleDownOnAbort:
+                type: boolean
               selector:
                 properties:
                   matchExpressions:
diff --git a/pkg/apiclient/rollout/rollout.swagger.json b/pkg/apiclient/rollout/rollout.swagger.json
index f984d322c2..d1cb053328 100644
--- a/pkg/apiclient/rollout/rollout.swagger.json
+++ b/pkg/apiclient/rollout/rollout.swagger.json
@@ -1155,6 +1155,10 @@
         "restartAt": {
           "$ref": "#/definitions/k8s.io.apimachinery.pkg.apis.meta.v1.Time",
           "title": "RestartAt indicates when all the pods of a Rollout should be restarted"
+        },
+        "scaleDownOnAbort": {
+          "type": "boolean",
+          "title": "ScaleDownOnAbort scales down"
         }
       },
       "title": "RolloutSpec is the spec for a Rollout resource"
diff --git a/pkg/apis/rollouts/v1alpha1/types.go b/pkg/apis/rollouts/v1alpha1/types.go
index 4836ef4026..272cd90fcf 100644
--- a/pkg/apis/rollouts/v1alpha1/types.go
+++ b/pkg/apis/rollouts/v1alpha1/types.go
@@ -71,6 +71,8 @@ type RolloutSpec struct {
 	ProgressDeadlineSeconds *int32 `json:"progressDeadlineSeconds,omitempty" protobuf:"varint,8,opt,name=progressDeadlineSeconds"`
 	// RestartAt indicates when all the pods of a Rollout should be restarted
 	RestartAt *metav1.Time `json:"restartAt,omitempty" protobuf:"bytes,9,opt,name=restartAt"`
+	// ScaleDownOnAbort scales down
+	ScaleDownOnAbort bool `json:"scaleDownOnAbort,omitempty" protobuf:"varint,11,opt,name=scaleDownOnAbort"`
 }
 
 func (s *RolloutSpec) SetResolvedSelector(selector *metav1.LabelSelector) {
diff --git a/rollout/bluegreen.go b/rollout/bluegreen.go
index 4fb7b2beba..b7e370fa08 100644
--- a/rollout/bluegreen.go
+++ b/rollout/bluegreen.go
@@ -30,6 +30,32 @@ func (c *rolloutContext) rolloutBlueGreen() error {
 		return c.syncRolloutStatusBlueGreen(previewSvc, activeSvc)
 	}
 
+	/*
+		if c.newRS != nil {
+			c.log.Infof("hkang: reconcileBlueGreenReplicaSets, newRS '%s'", c.newRS.Name)
+			if c.scaleDownOnAbort {
+				if c.pauseContext.IsAborted() {
+					c.log.Info("hkang: ctx status is aborted")
+					_, ok := c.newRS.Annotations[v1alpha1.DefaultReplicaSetScaleDownDeadlineAnnotationKey]
+					if !ok {
+						c.log.Info("hkang: addScaleDownDelay")
+						err := c.addScaleDownDelay(c.newRS)
+						if err != nil {
+							return err
+						}
+						return err
+					} else {
+						c.log.Info("hkang: addScaleDownDelay already set")
+					}
+				} else {
+					c.log.Info("hkang: ctx status is not aborted")
+				}
+			}
+		} else {
+			c.log.Info("hkang: newRS is nil")
+		}
+	*/
+
 	err = c.podRestarter.Reconcile(c)
 	if err != nil {
 		return err
@@ -98,6 +124,34 @@ func (c *rolloutContext) reconcileBlueGreenReplicaSets(activeSvc *corev1.Service
 	if err != nil {
 		return err
 	}
+
+	// Scale down newRS if aborted
+	/*
+		if c.newRS != nil {
+			c.log.Infof("hkang: reconcileBlueGreenReplicaSets, newRS '%s'", c.newRS.Name)
+			if c.scaleDownOnAbort {
+				if c.pauseContext.IsAborted() {
+					c.log.Info("hkang: ctx status is aborted")
+					_, ok := c.newRS.Annotations[v1alpha1.DefaultReplicaSetScaleDownDeadlineAnnotationKey]
+					if !ok {
+						c.log.Info("hkang: addScaleDownDelay")
+						err := c.addScaleDownDelay(c.newRS)
+						if err != nil {
+							return err
+						}
+						return err
+					} else {
+						c.log.Info("hkang: addScaleDownDelay already set")
+					}
+				} else {
+					c.log.Info("hkang: ctx status is not aborted")
+				}
+			}
+		} else {
+			c.log.Info("hkang: newRS is nil")
+		}
+	*/
+
 	if err := c.reconcileRevisionHistoryLimit(c.otherRSs); err != nil {
 		return err
 	}
@@ -318,7 +372,7 @@ func (c *rolloutContext) syncRolloutStatusBlueGreen(previewSvc *corev1.Service,
 	return c.persistRolloutStatus(&newStatus)
 }
 
-// calculateScaleUpPreviewCheckPoint calculates the correct value of status.blueGreen.scaleUpPreviewCheckPoint
+// calculateScaleUpPreviewCheckPoint calculates the correct value of status.blueGreen.scaleUpP	reviewCheckPoint
 // which is used by the blueGreen.previewReplicaCount feature. scaleUpPreviewCheckPoint is a single
 // direction trip-wire, initialized to false, and gets flipped true as soon as the preview replicas
 // matches scaleUpPreviewCheckPoint and prePromotionAnalysis (if used) completes. It get reset to
diff --git a/rollout/context.go b/rollout/context.go
index f21eaf4c8d..7cbcff85f9 100644
--- a/rollout/context.go
+++ b/rollout/context.go
@@ -46,6 +46,8 @@ type rolloutContext struct {
 	// we only perform weight verification when we are at a setWeight step since we do not want to
 	// continually verify weight in case it could incur rate-limiting or other expenses.
 	weightVerified *bool
+
+	// scaleDownOnAbort bool
 }
 
 func (c *rolloutContext) reconcile() error {
diff --git a/rollout/controller.go b/rollout/controller.go
index ca2dd141b5..87ed46a743 100644
--- a/rollout/controller.go
+++ b/rollout/controller.go
@@ -454,6 +454,7 @@ func (c *Controller) newRolloutContext(rollout *v1alpha1.Rollout) (*rolloutConte
 			log:     logCtx,
 		},
 		reconcilerBase: c.reconcilerBase,
+		// scaleDownOnAbort: false, // switch to true for dev
 	}
 	return &roCtx, nil
 }
diff --git a/rollout/replicaset.go b/rollout/replicaset.go
index d3d30f0718..1556127ee4 100644
--- a/rollout/replicaset.go
+++ b/rollout/replicaset.go
@@ -94,10 +94,17 @@ func (c *Controller) getReplicaSetsForRollouts(r *v1alpha1.Rollout) ([]*appsv1.R
 // removeScaleDownDelays removes the scale-down-deadline annotation from the new/stable ReplicaSets,
 // in the event that we moved back to an older revision that is still within its scaleDownDelay.
 func (c *rolloutContext) removeScaleDownDeadlines() error {
+	c.log.Info("hkang removeScaleDownDeadlines")
 	var toRemove []*appsv1.ReplicaSet
+	// if c.newRS != nil && !c.pauseContext.IsAborted() {
 	if c.newRS != nil {
+		c.log.Info("hkang remove scaleDown annotation in newRS")
 		toRemove = append(toRemove, c.newRS)
 	}
+	//} else {
+	c.log.Info("hkang DON'T remove scaleDown annotation in newRS")
+	//}
+
 	if c.stableRS != nil {
 		if len(toRemove) == 0 || c.stableRS.Name != c.newRS.Name {
 			toRemove = append(toRemove, c.stableRS)
@@ -116,14 +123,53 @@ func (c *rolloutContext) reconcileNewReplicaSet() (bool, error) {
 	if c.newRS == nil {
 		return false, nil
 	}
-	newReplicasCount, err := replicasetutil.NewRSNewReplicas(c.rollout, c.allRSs, c.newRS)
+	newReplicasCount := int32(0)
+	newIntendedReplicasCount, err := replicasetutil.NewRSNewReplicas(c.rollout, c.allRSs, c.newRS)
 	if err != nil {
 		return false, err
 	}
+
+	// if newRS is set to scaled down
+	scaleDownAtStr, scaleDownAnnotationAvailable := c.newRS.Annotations[v1alpha1.DefaultReplicaSetScaleDownDeadlineAnnotationKey]
+	c.log.Infof("hkang reconcileNewReplicaset: scaledown %v (%v)", scaleDownAtStr, scaleDownAnnotationAvailable)
+	// if scaleDownAnnotationAvailable && c.scaleDownOnAbort {
+	if c.pauseContext.IsAborted() && c.rollout.Spec.ScaleDownOnAbort {
+		c.log.Infof("hkang scaledown on abort '%s'", c.newRS.Name)
+		/*
+			scaleDownAtTime, err := time.Parse(time.RFC3339, scaleDownAtStr)
+			if err != nil {
+				c.log.Infof("hkang No scaleDownAt label on new rs '%s'", c.newRS.Name)
+			}
+			newReplicasCount = c.determineReplicaSetCountWhenScaling(c.newRS, newReplicasCount, newReplicasCount, scaleDownAtTime)
+		*/
+	} else {
+		newReplicasCount = newIntendedReplicasCount
+	}
+
+	c.log.Infof("hkang scaleReplicaSetAndRecordEvent '%d'", newReplicasCount)
 	scaled, _, err := c.scaleReplicaSetAndRecordEvent(c.newRS, newReplicasCount)
 	return scaled, err
 }
 
+// helper to handle the replica set scale down time
+// if the scale down time has not passed, enqueue the rollout
+func (c *rolloutContext) determineReplicaSetCountWhenScaling(targetRS *appsv1.ReplicaSet, defaultReplicaCount int32, desiredReplicaCount int32, scaleDownAtTime time.Time) int32 {
+	now := metav1.Now()
+	scaleDownAt := metav1.NewTime(scaleDownAtTime)
+	if scaleDownAt.After(now.Time) {
+		remainingTime := scaleDownAt.Sub(now.Time)
+		if remainingTime < c.resyncPeriod {
+			// if the scale down time has not passed, enqueue the rollout
+			c.log.Infof("hkang RS '%s' has not reached the scaleDownTime(remainingTime %s)", targetRS.Name, remainingTime)
+			c.enqueueRolloutAfter(c.rollout, remainingTime)
+		}
+		// set the replica count to be the desired replica count
+		return desiredReplicaCount
+	}
+	// if it's after the scale down time
+	return defaultReplicaCount
+}
+
 // reconcileOtherReplicaSets reconciles "other" ReplicaSets.
 // Other ReplicaSets are ReplicaSets are neither the new or stable (allRSs - newRS - stableRS)
 func (c *rolloutContext) reconcileOtherReplicaSets() (bool, error) {
diff --git a/utils/replicaset/canary.go b/utils/replicaset/canary.go
index 701c842a26..3a1e076170 100644
--- a/utils/replicaset/canary.go
+++ b/utils/replicaset/canary.go
@@ -297,6 +297,11 @@ func GetCanaryReplicasOrWeight(rollout *v1alpha1.Rollout) (*int32, int32) {
 		return nil, 100
 	}
 	if scs := UseSetCanaryScale(rollout); scs != nil {
+		if rollout.Status.Abort && rollout.Spec.ScaleDownOnAbort {
+			log.Info("hkang ScaleDownOnAbort is true")
+			return nil, 0
+		}
+
 		if scs.Replicas != nil {
 			return scs.Replicas, 0
 		} else if scs.Weight != nil {