Item object copy_feature_layer_collection() method does not work if there are relationships set (2.4.3)

[Clubdebambos]

Describe the bug
Item object copy_feature_layer_collection() method does not work if there are relationships set. Without a relationship for any of the feature layer and tables it works just fine, but attempt with a relationship for a layer/table and it fails. Testing from standalone script and AGOL Notebook.

To Reproduce
Steps to reproduce the behavior:

from arcgis.gis import GIS

## the name of the new service to create
new_service_name = "TESTING_DEEP_COPY"

## the item id of the service to copy
item_id = "FS_ITEM_ID"

agol = GIS("home")

item = agol.content.get(item_id)

## get the layer indexes
layers = list(range(len(item.layers)))

## get the table indexes
tables = list(range(len(item.tables)))

## copy the item - copies the shell, not data is added to the layers/tables
copied_item = item.copy_feature_layer_collection(
    service_name = new_service_name,
    layers = layers,
    tables = tables,
    description = item.description,
    snippet = item.snippet
)

error:

Traceback (most recent call last):
  File "C:\Users\glenb\Documents\Blogs\AGOL\Deepcopy_of_FLC\deepcopy_of_flc_maintain.py", line 48, in <module>
    copied_item = item.copy_feature_layer_collection(
        service_name = new_service_name,
    ...<3 lines>...
        snippet = item.snippet
    )
  File "C:\Program Files\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\Lib\site-packages\arcgis\gis\__init__.py", line 15631, in copy_feature_layer_collection
    res = fs_manager.add_to_definition(json_dict=add_defs)
  File "C:\Program Files\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\Lib\site-packages\arcgis\features\managers.py", line 3165, in add_to_definition
    res = self._con.post(adddefn_url, params)
  File "C:\Program Files\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\Lib\site-packages\arcgis\gis\_impl\_con\_connection.py", line 1530, in post
    return self._handle_response(
           ~~~~~~~~~~~~~~~~~~~~~^
        resp=resp,
        ^^^^^^^^^^
    ...<3 lines>...
        force_bytes=kwargs.pop("force_bytes", False),
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "C:\Program Files\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\Lib\site-packages\arcgis\gis\_impl\_con\_connection.py", line 1005, in _handle_response
    self._handle_json_error(data["error"], errorcode)
    ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Program Files\ArcGIS\Pro\bin\Python\envs\arcgispro-py3\Lib\site-packages\arcgis\gis\_impl\_con\_connection.py", line 1028, in _handle_json_error
    raise Exception(errormessage)
Exception: Unable to add feature service definition.
Invalid definition for System.Collections.Generic.List`1[ESRI.ArcGIS.SDS.Metadata.LayerCoreInfo]
Exception has been thrown by the target of an invocation.
(Error Code: 400)

Screenshots
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Expected behavior
I expect the copy_feature_layer_collection() to do as it should whether relationships are set or not, or at least stipulate that this is a limitation and handle it gracefully rather than erroring.

Platform (please complete the following information):

• OS: Windows 11
• Browser: Chrome/Edge
• Python API Version: 2.4.3

Additional context
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