/enums/value_rule_set_dimension.proto 

--- v17/enums/value_rule_set_dimension.proto    2024-10-17 03:48:51.000000000 +0000
+++ v18/enums/value_rule_set_dimension.proto    2024-10-17 03:48:56.000000000 +0000
@@ -49,5 +49,8 @@

     // This dimension implies the rule will always apply.
     NO_CONDITION = 5;
+
+    // Dimension for itinerary.
+    ITINERARY = 6;
   }
 }