ASCP Planned Order Implement As

Hi

I have a number of OSP type tems that are set up as make items.

The majority of these release from the ASCP workbench as expected where the Implement AS field defaults to a work order but there are some items where the default is NONE.

It does allow me to select work order in the LOV.

What set up am i missing for the items not to default to NONE but to work order when i select the release flag.

Thanks

Paul