diff --git a/openapi/openapiv2.json b/openapi/openapiv2.json
index fc1799d0..c636d7a0 100644
--- a/openapi/openapiv2.json
+++ b/openapi/openapiv2.json
@@ -5455,7 +5455,7 @@
         },
         "workflowStartDelay": {
           "type": "string",
-          "description": "Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`.\nIf the workflow gets a signal before the delay, a workflow task will be dispatched and the rest\nof the delay will be ignored."
+          "description": "Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`."
         },
         "completionCallbacks": {
           "type": "array",
@@ -10208,6 +10208,10 @@
         "inheritBuildId": {
           "type": "boolean",
           "description": "If this is set, the child workflow inherits the Build ID of the parent. Otherwise, the assignment\nrules of the child's Task Queue will be used to independently assign a Build ID to it."
+        },
+        "workflowStartDelay": {
+          "type": "string",
+          "description": "Time to wait before dispatching the child workflow's first task. Cannot\nbe used with `cron_schedule`."
         }
       }
     },
@@ -10325,6 +10329,10 @@
         "inheritBuildId": {
           "type": "boolean",
           "description": "If this is set, the child workflow inherits the Build ID of the parent. Otherwise, the assignment\nrules of the child's Task Queue will be used to independently assign a Build ID to it."
+        },
+        "workflowStartDelay": {
+          "type": "string",
+          "description": "Time to wait before dispatching the child workflow's first task. Cannot\nbe used with `cron_schedule`."
         }
       }
     },
@@ -10480,7 +10488,7 @@
         },
         "workflowStartDelay": {
           "type": "string",
-          "description": "Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`.\nIf the workflow gets a signal before the delay, a workflow task will be dispatched and the rest\nof the delay will be ignored."
+          "description": "Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`."
         },
         "completionCallbacks": {
           "type": "array",
diff --git a/openapi/openapiv3.yaml b/openapi/openapiv3.yaml
index 97a02043..0a7c2799 100644
--- a/openapi/openapiv3.yaml
+++ b/openapi/openapiv3.yaml
@@ -7925,6 +7925,12 @@ components:
           description: |-
             If this is set, the child workflow inherits the Build ID of the parent. Otherwise, the assignment
              rules of the child's Task Queue will be used to independently assign a Build ID to it.
+        workflowStartDelay:
+          pattern: ^-?(?:0|[1-9][0-9]{0,11})(?:\.[0-9]{1,9})?s$
+          type: string
+          description: |-
+            Time to wait before dispatching the child workflow's first task. Cannot
+             be used with `cron_schedule`.
     StartWorkflowExecutionRequest:
       type: object
       properties:
@@ -8018,10 +8024,7 @@ components:
         workflowStartDelay:
           pattern: ^-?(?:0|[1-9][0-9]{0,11})(?:\.[0-9]{1,9})?s$
           type: string
-          description: |-
-            Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`.
-             If the workflow gets a signal before the delay, a workflow task will be dispatched and the rest
-             of the delay will be ignored.
+          description: Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`.
         completionCallbacks:
           type: array
           items:
diff --git a/temporal/api/command/v1/message.proto b/temporal/api/command/v1/message.proto
index 3b8c9d9f..b0703809 100644
--- a/temporal/api/command/v1/message.proto
+++ b/temporal/api/command/v1/message.proto
@@ -226,6 +226,9 @@ message StartChildWorkflowExecutionCommandAttributes {
     // If this is set, the child workflow inherits the Build ID of the parent. Otherwise, the assignment
     // rules of the child's Task Queue will be used to independently assign a Build ID to it.
     bool inherit_build_id = 17;
+    // Time to wait before dispatching the child workflow's first task. Cannot
+    // be used with `cron_schedule`.
+    google.protobuf.Duration workflow_start_delay = 18;
 }
 
 message ProtocolMessageCommandAttributes {
diff --git a/temporal/api/history/v1/message.proto b/temporal/api/history/v1/message.proto
index 174d0869..af98d925 100644
--- a/temporal/api/history/v1/message.proto
+++ b/temporal/api/history/v1/message.proto
@@ -623,6 +623,9 @@ message StartChildWorkflowExecutionInitiatedEventAttributes {
     // If this is set, the child workflow inherits the Build ID of the parent. Otherwise, the assignment
     // rules of the child's Task Queue will be used to independently assign a Build ID to it.
     bool inherit_build_id = 19;
+    // Time to wait before dispatching the child workflow's first task. Cannot
+    // be used with `cron_schedule`.
+    google.protobuf.Duration workflow_start_delay = 20;
 }
 
 message StartChildWorkflowExecutionFailedEventAttributes {
diff --git a/temporal/api/workflowservice/v1/request_response.proto b/temporal/api/workflowservice/v1/request_response.proto
index f25e44f0..f55d8e59 100644
--- a/temporal/api/workflowservice/v1/request_response.proto
+++ b/temporal/api/workflowservice/v1/request_response.proto
@@ -186,8 +186,6 @@ message StartWorkflowExecutionRequest {
     temporal.api.failure.v1.Failure continued_failure = 18;
     temporal.api.common.v1.Payloads last_completion_result = 19;
     // Time to wait before dispatching the first workflow task. Cannot be used with `cron_schedule`.
-    // If the workflow gets a signal before the delay, a workflow task will be dispatched and the rest
-    // of the delay will be ignored.
     google.protobuf.Duration workflow_start_delay = 20;
     // Callbacks to be called by the server when this workflow reaches a terminal state.
     // If the workflow continues-as-new, these callbacks will be carried over to the new execution.