Finished Good sold from a partially completed Productn order

Dear all,

I have a question that needs advice.

Module: Advanced Management
Process: Manufacturing

Scenario:
We have a customer that has this requirement where they can sell finished goods that are partially completed from a production order that is still in progress.
Example, There is Production order for item X ( Finished Goods) Qty: 10 pcs. Then 6 pcs are completed. so we do an output journal to record the 6 pcs and put to Finished Good location, with 4 remaining. Please note that the item X is a brand new item, created for the first time where the unit cost is still empty (0).

Question:
1. why is the unit cost for the 6 pcs of item X not calculated and updated unless the production order status is changed to 'Finished'?

Scenario ( continue from the above scenario):
After the 6pcs of item X is available in the FG location with unit cost still 0 ( because the production order is in progress i.e status not changed to 'finished'/still 'released' , they are sold away. When we check the posted shipment journal, the value in the journal

Dr. COGS
Cr. Inventory

does not appear. But the journal will appear when the Production order's status is changed to 'finished'.

Question:
1. Is there a way or setting to have the value of the unit cost to be calculated and recorded, although the production order status is still 'released' i.e not 'finished'?

We tried to use the ' update unit cost' button but the unit cost field in item master is not updated.

FYI, we enable the expected cost posting and automatic cost adjustment to 'always' in Inventory set up menu.

Thank you for the advice.