autosmithing not allowing you to choose what you're smithing

so i have substantial reserves of both copper and tin; I go to autosmith and select tin, then do arrow tips. When I run out of tin on hand, Skia goes back to the bank for more ore, which is cool-- but she comes back with copper, and not tin.

In fact, if you have multiple types of ore on hand, it's not possible to actually specify what you're autosmithing.

I realize smithing and autosmithing are an interface nightmare but it's not much worth the cash grind if you're stuck using the lowest-tier ore available.