Ran a data integrity check and I now see the 4th Account Set included in the drop down.

I will pass the Most Recent Cost value to the Standard Cost and see what impact it has on my COGS calculations.

I am using Counter Sales (XS) with Adagio Inventory...

Real problem is that the clients inventory costing is "muddled" having previously operated standalone so the calculations which are coming from the XS to the Ledger are incorrect.

This is why I asked for the prior solution (Most Recent Cost).