diff --git a/dropbox/files.py b/dropbox/files.py
index 6a30a10..9bc620e 100644
--- a/dropbox/files.py
+++ b/dropbox/files.py
@@ -14788,7 +14788,7 @@ def _process_custom_annotations(self, annotation_type, field_path, processor):
 ]
 
 UploadSessionAppendBatchArg.entries.validator = bv.List(
-    UploadSessionAppendBatchArgEntry_validator, max_items=1000
+    UploadSessionAppendBatchArgEntry_validator, max_items=500
 )
 UploadSessionAppendBatchArg.content_hash.validator = bv.Nullable(Sha256HexHash_validator)
 UploadSessionAppendBatchArg._all_field_names_ = set(
diff --git a/spec b/spec
index 85c818f..1617b30 160000
--- a/spec
+++ b/spec
@@ -1 +1 @@
-Subproject commit 85c818f60ef2afd5acf469cea0683183da8958a3
+Subproject commit 1617b302665c6868552a03fe8f8bc51023411a19