diff --git a/openfl/experimental/component/aggregator/aggregator.py b/openfl/experimental/component/aggregator/aggregator.py
index e9e2fb20985..b2c4e34eab8 100644
--- a/openfl/experimental/component/aggregator/aggregator.py
+++ b/openfl/experimental/component/aggregator/aggregator.py
@@ -121,7 +121,7 @@ def __set_attributes_to_clone(self, clone: Any) -> None:
             for name, attr in self.__private_attrs.items():
                 setattr(clone, name, attr)
 
-    def __delete_agg_attrs_from_clone(self, clone: Any) -> None:
+    def __delete_agg_attrs_from_clone(self, clone: Any, replace_str: str = None) -> None:
         """
         Remove aggregator private attributes from FLSpec clone before
         transition from Aggregator step to collaborator steps.
@@ -132,7 +132,10 @@ def __delete_agg_attrs_from_clone(self, clone: Any) -> None:
             for attr_name in self.__private_attrs:
                 if hasattr(clone, attr_name):
                     self.__private_attrs.update({attr_name: getattr(clone, attr_name)})
-                    delattr(clone, attr_name)
+                    if replace_str:
+                        setattr(clone, attr_name, replace_str)
+                    else:
+                        delattr(clone, attr_name)
 
     def _log_big_warning(self) -> None:
         """Warn user about single collaborator cert mode."""
@@ -221,11 +224,6 @@ def call_checkpoint(self, ctx: Any, f: Callable, stream_buffer: bytes = None,
                 # Set stream buffer as function parameter
                 setattr(f.__func__, "_stream_buffer", pickle.loads(stream_buffer))
 
-            # Replce reserved attribute values with string
-            for attr in reserved_attributes:
-                if hasattr(ctx, attr):
-                    setattr(ctx, attr, "Private attributes: Not Available.")
-
             checkpoint(ctx, f)
 
     def get_tasks(self, collaborator_name: str) -> Tuple:
@@ -288,7 +286,7 @@ def do_task(self, f_name: str) -> Any:
             if f.__name__ == "end":
                 f()
                 # Take the checkpoint of "end" step
-                self.__delete_agg_attrs_from_clone(self.flow)
+                self.__delete_agg_attrs_from_clone(self.flow, "Private attributes: Not Available.")
                 self.call_checkpoint(self.flow, f)
                 self.__set_attributes_to_clone(self.flow)
                 # self.call_checkpoint(deepcopy(self.flow), f,
diff --git a/openfl/experimental/component/collaborator/collaborator.py b/openfl/experimental/component/collaborator/collaborator.py
index e90a467c069..044ce128474 100644
--- a/openfl/experimental/component/collaborator/collaborator.py
+++ b/openfl/experimental/component/collaborator/collaborator.py
@@ -83,7 +83,7 @@ def __set_attributes_to_clone(self, clone: Any) -> None:
             for name, attr in self.__private_attrs.items():
                 setattr(clone, name, attr)
 
-    def __delete_agg_attrs_from_clone(self, clone: Any) -> None:
+    def __delete_agg_attrs_from_clone(self, clone: Any, replace_str: str = None) -> None:
         """
         Remove aggregator private attributes from FLSpec clone before
         transition from Aggregator step to collaborator steps
@@ -101,7 +101,10 @@ def __delete_agg_attrs_from_clone(self, clone: Any) -> None:
             for attr_name in self.__private_attrs:
                 if hasattr(clone, attr_name):
                     self.__private_attrs.update({attr_name: getattr(clone, attr_name)})
-                    delattr(clone, attr_name)
+                    if replace_str:
+                        setattr(clone, attr_name, replace_str)
+                    else:
+                        delattr(clone, attr_name)
 
     def call_checkpoint(self, ctx: Any, f: Callable, stream_buffer: Any) -> None:
         """
@@ -117,8 +120,7 @@ def call_checkpoint(self, ctx: Any, f: Callable, stream_buffer: Any) -> None:
         """
         self.client.call_checkpoint(
             self.name,
-            deepcopy(ctx), pickle.dumps(f), pickle.dumps(stream_buffer),
-            list(self.__private_attrs.keys())
+            pickle.dumps(ctx), pickle.dumps(f), pickle.dumps(stream_buffer)
         )
 
     def run(self) -> None:
@@ -200,7 +202,9 @@ def do_task(self, f_name: str, ctx: Any) -> Tuple:
             f = getattr(ctx, f_name)
             f()
             # Checkpoint the function
+            self.__delete_agg_attrs_from_clone(ctx, "Private attributes: Not Available.")
             self.call_checkpoint(ctx, f, f._stream_buffer)
+            self.__set_attributes_to_clone(ctx)
 
             _, f, parent_func = ctx.execute_task_args[:3]
             # Display transition logs if transition
diff --git a/openfl/experimental/transport/grpc/aggregator_client.py b/openfl/experimental/transport/grpc/aggregator_client.py
index afcc6d1bf94..82458792772 100644
--- a/openfl/experimental/transport/grpc/aggregator_client.py
+++ b/openfl/experimental/transport/grpc/aggregator_client.py
@@ -304,20 +304,10 @@ def get_tasks(self, collaborator_name):
 
     @_atomic_connection
     @_resend_data_on_reconnection
-    def call_checkpoint(self, collaborator_name, ctx, function, stream_buffer, private_attrs):
+    def call_checkpoint(self, collaborator_name, clone_bytes, function, stream_buffer):
         """Perform checkpoint for collaborator task."""
         self._set_header(collaborator_name)
 
-        # Remove private attributes from context
-        if len(private_attrs) > 0:
-            import pickle
-
-            for attr in private_attrs:
-                if hasattr(ctx, attr):
-                    setattr(ctx, attr, "Private attributes: Not Available.")
-
-            clone_bytes = pickle.dumps(ctx)
-
         request = aggregator_pb2.CheckpointRequest(
             header=self.header,
             execution_environment=clone_bytes,