diff --git a/agent/Dockerfile b/agent/Dockerfile
index d6fdba85..33e9d5e7 100644
--- a/agent/Dockerfile
+++ b/agent/Dockerfile
@@ -341,7 +341,7 @@ ENTRYPOINT ["/usr/local/bin/snapshot-agent"]
 # PATH search — and so must this placeholder image (same BASE_IMAGE).
 #
 # Backend entrypoints run a restore standby path when the operator
-# injects DYN_SNAPSHOT_RESTORE_STANDBY=1, then sleep while the
+# injects SNAPSHOT_RESTORE_STANDBY=1, then sleep while the
 # snapshot-agent restores into the container.
 # =============================================================================
 FROM ${BASE_IMAGE} AS placeholder
diff --git a/api/v1alpha1/constants.go b/api/v1alpha1/constants.go
index 2d2c32ac..c46c6d66 100644
--- a/api/v1alpha1/constants.go
+++ b/api/v1alpha1/constants.go
@@ -63,10 +63,25 @@ const (
 	// this name) keep working while new images can move to
 	// SnapshotControlDirEnv.
 	//
-	// Deprecated: use SnapshotControlDirEnv instead. Remove once no workload
-	// image depends on this name.
+	// Use SnapshotControlDirEnv for new workload images. Remove this legacy
+	// name once no workload image depends on it.
 	LegacySnapshotControlDirEnv = "DYN_SNAPSHOT_CONTROL_DIR"
 
+	// RestoreStandbyModeEnv asks standby-aware workload entrypoints to capture
+	// restore context and sleep instead of cold-starting the workload. Generic
+	// images that do not honor this env must still provide their own inert
+	// restore command.
+	RestoreStandbyModeEnv = "SNAPSHOT_RESTORE_STANDBY"
+
+	// LegacyRestoreStandbyModeEnv is the deprecated restore standby env var.
+	// Restore pod shaping injects both names during the migration window so
+	// existing workload images keep working while new images move to
+	// RestoreStandbyModeEnv.
+	//
+	// Use RestoreStandbyModeEnv for new workload images. Remove this legacy
+	// name once no workload image depends on it.
+	LegacyRestoreStandbyModeEnv = "DYN_SNAPSHOT_RESTORE_STANDBY"
+
 	// SnapshotCompleteFile named the sentinel the agent used to release a
 	// checkpointed workload when leave-running dumps existed. A checkpoint now
 	// always terminates the source process, so the agent no longer writes it;
diff --git a/e2e/snapshot_e2e/workloads.py b/e2e/snapshot_e2e/workloads.py
index cd40b798..200812f0 100644
--- a/e2e/snapshot_e2e/workloads.py
+++ b/e2e/snapshot_e2e/workloads.py
@@ -93,7 +93,7 @@ def restore_pod(
         }
     }
     spec["containers"][0]["env"] = [
-        {"name": "DYN_SNAPSHOT_RESTORE_STANDBY", "value": "1"},
+        {"name": "SNAPSHOT_RESTORE_STANDBY", "value": "1"},
         {"name": "SNAPSHOT_CONTROL_DIR", "value": CONTROL_DIR},
         {"name": RESTORE_TOKEN_ENV, "value": run.restore_token},
     ]
@@ -153,7 +153,7 @@ def multi_restore_pod(
                 }
             ],
             "env": [
-                {"name": "DYN_SNAPSHOT_RESTORE_STANDBY", "value": "1"},
+                {"name": "SNAPSHOT_RESTORE_STANDBY", "value": "1"},
                 {"name": "SNAPSHOT_CONTROL_DIR", "value": CONTROL_DIR},
                 {"name": RESTORE_TOKEN_ENV, "value": restore_tokens[destination]},
             ],
diff --git a/operator/internal/protocol/restore.go b/operator/internal/protocol/restore.go
index fa917158..5e4f63a9 100644
--- a/operator/internal/protocol/restore.go
+++ b/operator/internal/protocol/restore.go
@@ -19,14 +19,7 @@ type PodOptions struct {
 	SeccompProfile  string
 }
 
-const (
-	// RestoreStandbyModeEnv asks standby-aware workload entrypoints to capture
-	// restore context and sleep instead of cold-starting the workload. Generic
-	// images that do not honor this env must still provide their own inert
-	// restore command.
-	RestoreStandbyModeEnv          = "DYN_SNAPSHOT_RESTORE_STANDBY"
-	restoreStartupFailureThreshold = 1800 // 30 minutes at 1s cadence.
-)
+const restoreStartupFailureThreshold = 1800 // 30 minutes at 1s cadence.
 
 // NewRestorePod shapes every annotated target container for restore.
 func NewRestorePod(pod *corev1.Pod, opts PodOptions) (*corev1.Pod, error) {
@@ -55,7 +48,7 @@ func NewRestorePod(pod *corev1.Pod, opts PodOptions) (*corev1.Pod, error) {
 
 // PrepareRestorePodSpec applies restore shaping to annotated target containers.
 // It does not change container command/args. Once the checkpoint is ready, it
-// sets DYN_SNAPSHOT_RESTORE_STANDBY=1 so standby-aware workload entrypoints
+// sets SNAPSHOT_RESTORE_STANDBY=1 so standby-aware workload entrypoints
 // sleep before CRIU restore; generic images that do not honor the env must
 // still provide their own inert restore command.
 func PrepareRestorePodSpec(
@@ -92,27 +85,25 @@ func PrepareRestorePodSpec(
 			// Standby-aware entrypoints honor this env by writing restore
 			// context and sleeping. Keep command/args intact so generic images
 			// can provide their own inert restore entrypoint when needed.
-			foundRestoreStandbyModeEnv := false
-			for i := range container.Env {
-				if container.Env[i].Name == RestoreStandbyModeEnv {
-					container.Env[i].Value = "1"
-					container.Env[i].ValueFrom = nil
-					foundRestoreStandbyModeEnv = true
-					break
-				}
-			}
-			if !foundRestoreStandbyModeEnv {
-				container.Env = append(container.Env, corev1.EnvVar{
-					Name:  RestoreStandbyModeEnv,
-					Value: "1",
-				})
-			}
+			ensureEnvValue(container, snapshotv1alpha1.RestoreStandbyModeEnv, "1")
+			ensureEnvValue(container, snapshotv1alpha1.LegacyRestoreStandbyModeEnv, "1")
 			ensureRestoreStartupProbe(container)
 		}
 	}
 	return nil
 }
 
+func ensureEnvValue(container *corev1.Container, name, value string) {
+	for i := range container.Env {
+		if container.Env[i].Name == name {
+			container.Env[i].Value = value
+			container.Env[i].ValueFrom = nil
+			return
+		}
+	}
+	container.Env = append(container.Env, corev1.EnvVar{Name: name, Value: value})
+}
+
 // ensureRestoreStartupProbe installs a StartupProbe that gates Ready until
 // CRIU restore completes. It prefers the workload's existing Startup/Liveness/
 // Readiness probe (deep-copied with tightened cadence and infinite retries),
diff --git a/operator/internal/protocol/restore_test.go b/operator/internal/protocol/restore_test.go
index bf1db580..cfb3d0d1 100644
--- a/operator/internal/protocol/restore_test.go
+++ b/operator/internal/protocol/restore_test.go
@@ -52,7 +52,8 @@ func TestNewRestorePodSetsRestoreFromAnnotation(t *testing.T) {
 	main := &pod.Spec.Containers[0]
 	assert.Equal(t, []string{"python3"}, main.Command)
 	assert.Equal(t, []string{"serve.py"}, main.Args)
-	assert.Equal(t, "1", envValue(main.Env, RestoreStandbyModeEnv))
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
 	assert.Equal(t, snapshotv1alpha1.SnapshotControlMountPath, main.VolumeMounts[0].MountPath)
 	assert.Equal(t, "main", main.VolumeMounts[0].SubPath)
 	require.NotNil(t, main.StartupProbe)
@@ -80,7 +81,33 @@ func TestPrepareRestorePodSpecIsIdempotent(t *testing.T) {
 	main := &spec.Containers[0]
 	assert.Len(t, spec.Volumes, 1)
 	assert.Len(t, main.VolumeMounts, 1)
-	assert.Equal(t, "1", envValue(main.Env, RestoreStandbyModeEnv))
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
+	assert.Equal(t, 1, envCount(main.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+	assert.Equal(t, 1, envCount(main.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
+}
+
+func TestPrepareRestorePodSpecAddsCanonicalStandbyEnvWhenLegacyExists(t *testing.T) {
+	spec := restorePodFixture().Spec
+	spec.Containers[0].Env = []corev1.EnvVar{{
+		Name: snapshotv1alpha1.LegacyRestoreStandbyModeEnv,
+		ValueFrom: &corev1.EnvVarSource{
+			FieldRef: &corev1.ObjectFieldSelector{FieldPath: "metadata.name"},
+		},
+	}}
+
+	require.NoError(t, PrepareRestorePodSpec(&spec, restoreMappings("main"), "", true))
+
+	main := &spec.Containers[0]
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+	assert.Equal(t, "1", envValue(main.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
+	assert.Equal(t, 1, envCount(main.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+	assert.Equal(t, 1, envCount(main.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
+	for _, item := range main.Env {
+		if item.Name == snapshotv1alpha1.LegacyRestoreStandbyModeEnv {
+			assert.Nil(t, item.ValueFrom)
+		}
+	}
 }
 
 func TestPrepareRestorePodSpecReusesExistingProbe(t *testing.T) {
@@ -140,7 +167,8 @@ func TestNewRestorePodShapesMappedDestinations(t *testing.T) {
 		require.Equal(t, name, container.Name)
 		require.Len(t, container.VolumeMounts, 1)
 		assert.Equal(t, name, container.VolumeMounts[0].SubPath)
-		assert.Equal(t, "1", envValue(container.Env, RestoreStandbyModeEnv))
+		assert.Equal(t, "1", envValue(container.Env, snapshotv1alpha1.RestoreStandbyModeEnv))
+		assert.Equal(t, "1", envValue(container.Env, snapshotv1alpha1.LegacyRestoreStandbyModeEnv))
 		require.NotNil(t, container.StartupProbe)
 	}
 }
@@ -170,3 +198,13 @@ func envValue(env []corev1.EnvVar, name string) string {
 	}
 	return ""
 }
+
+func envCount(env []corev1.EnvVar, name string) int {
+	count := 0
+	for _, item := range env {
+		if item.Name == name {
+			count++
+		}
+	}
+	return count
+}