diff --git a/simvue/api/objects/alert/base.py b/simvue/api/objects/alert/base.py
index 1990a00c..5c3953cb 100644
--- a/simvue/api/objects/alert/base.py
+++ b/simvue/api/objects/alert/base.py
@@ -31,7 +31,12 @@ def __init__(self, identifier: str | None = None, **kwargs) -> None:
         """Retrieve an alert from the Simvue server by identifier"""
         self._label = "alert"
         super().__init__(identifier=identifier, **kwargs)
-        self._local_only_args = ["frequency", "pattern", "aggregation"]
+        self._local_only_args = [
+            "frequency",
+            "pattern",
+            "aggregation",
+            "status",
+        ]
 
     def compare(self, other: "AlertBase") -> bool:
         """Compare this alert to another"""
diff --git a/simvue/api/objects/base.py b/simvue/api/objects/base.py
index 679b473f..4c0bdc86 100644
--- a/simvue/api/objects/base.py
+++ b/simvue/api/objects/base.py
@@ -201,7 +201,7 @@ def __init__(
         # For simvue object initialisation, unlike the server there is no nested
         # arguments, however this means that there are extra keys during post which
         # need removing, this attribute handles that and should be set in subclasses.
-        self._local_only_args: list[str] = []
+        self._local_only_args: list[str] = ["created"]
 
         self._identifier: str | None = (
             identifier if identifier is not None else f"offline_{uuid.uuid1()}"
@@ -636,13 +636,13 @@ def _post_batch(
     def _post_single(
         self, *, is_json: bool = True, data: list | dict | None = None, **kwargs
     ) -> dict[str, typing.Any] | list[dict[str, typing.Any]]:
-        if not is_json:
-            kwargs = msgpack.packb(data or kwargs, use_bin_type=True)
-
         # Remove any extra keys
         for key in self._local_only_args:
             _ = (data or kwargs).pop(key, None)
 
+        if not is_json:
+            kwargs = msgpack.packb(data or kwargs, use_bin_type=True)
+
         _response = sv_post(
             url=f"{self._base_url}",
             headers=self._headers | {"Content-Type": "application/msgpack"},
diff --git a/simvue/api/objects/storage/s3.py b/simvue/api/objects/storage/s3.py
index 87ff3c3c..c4c522cc 100644
--- a/simvue/api/objects/storage/s3.py
+++ b/simvue/api/objects/storage/s3.py
@@ -27,6 +27,13 @@ def __init__(self, identifier: str | None = None, **kwargs) -> None:
         """Initialise an S3Storage instance attaching a configuration"""
         self.config = Config(self)
         super().__init__(identifier, **kwargs)
+        self._local_only_args: list[str] = [
+            "endpoint_url",
+            "region_name",
+            "access_key_id",
+            "secret_access_key",
+            "bucket",
+        ]
 
     @classmethod
     @pydantic.validate_call