Location priority for stock deduction

Hi,

I am wondering how to deduct stock from a specific location first. I see that there is an option to set Location priority, but it looks like that is not working, or its use is for something else.

So, what I want to do is:

1. have 2 stock locations – 01 and 02
2. when I sell something I want that stock deducts from location 01 first until that location is empty. Then, location 02 comes in and its stock is used.

I also see, when I have a product opened, that next to location name is a small circle which says: “Make Term Primary”

If I do that, then deduction priority works.

Now, what I would like to do is to set this by using location priority. Is that doable? I think I managed to do that at one of my staging websites, but now at the real one it does not work. I really do not know what I have done at staging, cos I deleted them.

Or, if I have to use “Make Term Primary” option, I would like to use WP all import for that, but I do not know the name of the custom field for that.

Could you tell me that?

I detected custom fields for stock locations (_stock_at_ID), but for this I have no idea.

Thanks,
M.