diff --git a/interfaces/astm/f3411/v19 b/interfaces/astm/f3411/v19
index 36e7ea2..228b301 160000
--- a/interfaces/astm/f3411/v19
+++ b/interfaces/astm/f3411/v19
@@ -1 +1 @@
-Subproject commit 36e7ea23a010ff91053f82ac4f6a9bfc698503f9
+Subproject commit 228b301be1f4466df9b014f20b515665861a8e67
diff --git a/interfaces/astm/f3411/v22a b/interfaces/astm/f3411/v22a
index 1007138..dd4016b 160000
--- a/interfaces/astm/f3411/v22a
+++ b/interfaces/astm/f3411/v22a
@@ -1 +1 @@
-Subproject commit 1007138177947b3b766f76bc867daf6de3ff0b61
+Subproject commit dd4016b09fc8cb98f30c2a17b5a088fb2995ab54
diff --git a/src/uas_standards/astm/f3411/v19/api.py b/src/uas_standards/astm/f3411/v19/api.py
index 5c8f986..3b03edf 100644
--- a/src/uas_standards/astm/f3411/v19/api.py
+++ b/src/uas_standards/astm/f3411/v19/api.py
@@ -356,7 +356,7 @@ class SearchSubscriptionsResponse(ImplicitDict):
 class SubscriptionState(ImplicitDict):
     """State of AreaSubscription which is causing a notification to be sent."""
 
-    subscription_id: Optional[SubscriptionUUID]
+    subscription_id: SubscriptionUUID
 
     notification_index: Optional[SubscriptionNotificationIndex]