On a not cash-and-carry retail sales order, the location is reset if several validations are passed.

RetailCreateCustomerOrderExtensions.allowResetRetailOrderLineWarehouse()

1. Line is not cash and carry.
2. Advanced Warehouse Management is enabled for the item.
3. Delivery mode is not empty.
4. Line is not a return.
5. Location is not empty.
6. Line is being newly added or current location id empty.

Validation 2 checks if an item is WHS enabled, but this check should be enhanced to validate if the warehouse is also WHS enabled.