Sales Channel And Warehouse Mapping: Many Internals To One External

Multiple internal sales channels can now map to a single external store on the same integration — for example, Faire USA and Faire Canada both pointing at one "Faire" store in ShipStation. Warehouse mappings work the same way (two internal buildings, one ShipStation ship-from address). Before, the mapping refused to save with an "already mapped" error, because a defensive uniqueness rule assumed one internal per external per integration.

The mapping modals have been inverted to match. The internal value is now the row, and the external ShipStation option is the dropdown — the reverse of the old layout. That's the shape you need to have many internals pointing at one external, since whichever side owns the rows is the side you can repeat. Each internal channel or building can still only claim one external key, so mistakes like the same building mapping twice are still caught.