yes sir, you use the button on the inventory detail. that would be the most basic way to create them.

I don't think there is an Inventory Detail button when you release a WO. It exists when you enter completion, but I need to create/pre-assign Serial numbers when the WO is Released.

Correct. Inventory Detail for the Assembly can only be set on the final completion as far as I know. We have a custom field on the Work Order body that stores an auto generated number (via a button and associated custom script). The field is also exposed on the Completion form, so users copy the value in the field and then paste into the Inventory Detail. Not ideal...

Got it. Thank you for sharing.