diff --git a/openapi/openapiv2.json b/openapi/openapiv2.json
index 5e0c615af..b24d412d0 100644
--- a/openapi/openapiv2.json
+++ b/openapi/openapiv2.json
@@ -7104,7 +7104,37 @@
           "format": "date-time"
         },
         "drainageStatus": {
-          "$ref": "#/definitions/v1VersionDrainageStatus"
+          "$ref": "#/definitions/v1VersionDrainageStatus",
+          "description": "Deprecated. Use `drainage_info` instead."
+        },
+        "drainageInfo": {
+          "$ref": "#/definitions/v1VersionDrainageInfo",
+          "title": "Information about workflow drainage to help the user determine when it is safe\nto decommission a Version. Not present while version is current or ramping"
+        },
+        "currentSinceTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Unset if not current."
+        },
+        "rampingSinceTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Unset if not ramping. Updated when the version first starts ramping, not on each ramp change."
+        },
+        "routingUpdateTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Last time `current_since_time`, `ramping_since_time, or `ramp_percentage` of this version changed."
+        },
+        "firstActivationTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when this version first became current or ramping."
+        },
+        "lastDeactivationTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when this version last stopped being current or ramping."
         }
       }
     },
@@ -14933,12 +14963,22 @@
         "currentSinceTime": {
           "type": "string",
           "format": "date-time",
-          "description": "\nNil if not current."
+          "description": "\nUnset if not current."
         },
         "rampingSinceTime": {
           "type": "string",
           "format": "date-time",
-          "description": "\nNil if not ramping. Updated when the version first starts ramping, not on each ramp change."
+          "description": "\nUnset if not ramping. Updated when the version first starts ramping, not on each ramp change."
+        },
+        "firstActivationTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when this version first became current or ramping."
+        },
+        "lastDeactivationTime": {
+          "type": "string",
+          "format": "date-time",
+          "description": "Timestamp when this version last stopped being current or ramping."
         },
         "rampPercentage": {
           "type": "number",
diff --git a/openapi/openapiv3.yaml b/openapi/openapiv3.yaml
index 28aab1cfb..7468f857e 100644
--- a/openapi/openapiv3.yaml
+++ b/openapi/openapiv3.yaml
@@ -12221,7 +12221,40 @@ components:
             - VERSION_DRAINAGE_STATUS_DRAINING
             - VERSION_DRAINAGE_STATUS_DRAINED
           type: string
+          description: Deprecated. Use `drainage_info` instead.
           format: enum
+        drainageInfo:
+          allOf:
+            - $ref: '#/components/schemas/VersionDrainageInfo'
+          description: |-
+            Information about workflow drainage to help the user determine when it is safe
+             to decommission a Version. Not present while version is current or ramping
+        currentSinceTime:
+          type: string
+          description: |-
+            Unset if not current.
+             (-- api-linter: core::0140::prepositions=disabled
+                 aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
+          format: date-time
+        rampingSinceTime:
+          type: string
+          description: |-
+            Unset if not ramping. Updated when the version first starts ramping, not on each ramp change.
+             (-- api-linter: core::0140::prepositions=disabled
+                 aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
+          format: date-time
+        routingUpdateTime:
+          type: string
+          description: Last time `current_since_time`, `ramping_since_time, or `ramp_percentage` of this version changed.
+          format: date-time
+        firstActivationTime:
+          type: string
+          description: Timestamp when this version first became current or ramping.
+          format: date-time
+        lastDeactivationTime:
+          type: string
+          description: Timestamp when this version last stopped being current or ramping.
+          format: date-time
     WorkerDeploymentOptions:
       type: object
       properties:
@@ -12290,14 +12323,22 @@ components:
           description: |-
             (-- api-linter: core::0140::prepositions=disabled
                  aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
-             Nil if not current.
+             Unset if not current.
           format: date-time
         rampingSinceTime:
           type: string
           description: |-
             (-- api-linter: core::0140::prepositions=disabled
                  aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
-             Nil if not ramping. Updated when the version first starts ramping, not on each ramp change.
+             Unset if not ramping. Updated when the version first starts ramping, not on each ramp change.
+          format: date-time
+        firstActivationTime:
+          type: string
+          description: Timestamp when this version first became current or ramping.
+          format: date-time
+        lastDeactivationTime:
+          type: string
+          description: Timestamp when this version last stopped being current or ramping.
           format: date-time
         rampPercentage:
           type: number
diff --git a/temporal/api/deployment/v1/message.proto b/temporal/api/deployment/v1/message.proto
index ead82fcdf..15b9230db 100644
--- a/temporal/api/deployment/v1/message.proto
+++ b/temporal/api/deployment/v1/message.proto
@@ -107,14 +107,19 @@ message WorkerDeploymentVersionInfo {
 
     // (-- api-linter: core::0140::prepositions=disabled
     //     aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
-    // Nil if not current.
+    // Unset if not current.
     google.protobuf.Timestamp current_since_time = 5;
 
     // (-- api-linter: core::0140::prepositions=disabled
     //     aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
-    // Nil if not ramping. Updated when the version first starts ramping, not on each ramp change.
+    // Unset if not ramping. Updated when the version first starts ramping, not on each ramp change.
     google.protobuf.Timestamp ramping_since_time = 6;
 
+    // Timestamp when this version first became current or ramping.
+    google.protobuf.Timestamp first_activation_time = 12;
+    // Timestamp when this version last stopped being current or ramping.
+    google.protobuf.Timestamp last_deactivation_time = 13;
+
     // Range: [0, 100]. Must be zero if the version is not ramping (i.e. `ramping_since_time` is nil).
     // Can be in the range [0, 100] if the version is ramping.
     float ramp_percentage = 7;
@@ -193,7 +198,25 @@ message WorkerDeploymentInfo {
         // Required.
         WorkerDeploymentVersion deployment_version = 4;
         google.protobuf.Timestamp create_time = 2;
+        // Deprecated. Use `drainage_info` instead.
         enums.v1.VersionDrainageStatus drainage_status = 3;
+        // Information about workflow drainage to help the user determine when it is safe
+        // to decommission a Version. Not present while version is current or ramping
+        VersionDrainageInfo drainage_info = 5;
+        // Unset if not current.
+        // (-- api-linter: core::0140::prepositions=disabled
+        //     aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
+        google.protobuf.Timestamp current_since_time = 6;
+        // Unset if not ramping. Updated when the version first starts ramping, not on each ramp change.
+        // (-- api-linter: core::0140::prepositions=disabled
+        //     aip.dev/not-precedent: 'Since' captures the field semantics despite being a preposition. --)
+        google.protobuf.Timestamp ramping_since_time = 7;
+        // Last time `current_since_time`, `ramping_since_time, or `ramp_percentage` of this version changed.
+        google.protobuf.Timestamp routing_update_time = 8;
+        // Timestamp when this version first became current or ramping.
+        google.protobuf.Timestamp first_activation_time = 9;
+        // Timestamp when this version last stopped being current or ramping.
+        google.protobuf.Timestamp last_deactivation_time = 10;
     }
 }