diff --git a/scripts/pb-add-dn-batches.py b/scripts/pb-add-dn-batches.py
index 3bc9eea..98cfbf7 100755
--- a/scripts/pb-add-dn-batches.py
+++ b/scripts/pb-add-dn-batches.py
@@ -69,6 +69,12 @@ def main():
         "name": "DN_BATCHES",
         "type": "base",
         "fields": [
+            # PB system fields — required so `sort=created` / `sort=-created`
+            # queries work (the tick route and the inbox page both sort on
+            # these). PB manages their values internally once the field
+            # names match.
+            {"name": "created", "type": "date", "required": False, "onCreate": True},
+            {"name": "updated", "type": "date", "required": False, "onCreate": True, "onUpdate": True},
             {"name": "file", "type": "file", "required": False, "maxSelect": 1, "maxSize": 20971520},
             {"name": "file_hash", "type": "text", "required": False},
             {"name": "site", "type": "relation", "required": True,
@@ -93,6 +99,8 @@ def main():
         "name": "DN_BATCH_NOTES",
         "type": "base",
         "fields": [
+            {"name": "created", "type": "date", "required": False, "onCreate": True},
+            {"name": "updated", "type": "date", "required": False, "onCreate": True, "onUpdate": True},
             {"name": "batch", "type": "relation", "required": True,
              "collectionId": batches_id, "maxSelect": 1, "cascadeDelete": True},
             {"name": "note_index", "type": "number", "required": False},