Copy Hierarchy to another Characteristic

Hi Guys

I would like to load the 0COSTELMNT hierarchies to my ZCOSTELMNT field. I need the hierarchies on both as one is a secondary cost element.

I cannot create the Z field as a reference characteristic of the 0 field as i need to use them in planning and this causes issues with the Characteristic Relationships (derivations) between the two.

How would I create an upload to the Z field for the hierarchies or how would I copy the hierarchies between characteristics? I'm hoping the answer is not download to flat file and upload!

Thanks

Gareth