So we’re using the variant.incoming attribute in our theme to display "Coming Soon" instead of "Sold Out" if there is incoming inventory.
However, we noticed when we created a transfer for some products but then deleted the transfer the variant.incoming is still "true" for those same products. Looking at the product in admin it shows Incoming: 0 so this must be some bug.
Also, more or less related: If you copy a product that is a in a transfer (and so has incoming inventory), the variant.incoming is also copied into the new product. This new product has variant.incoming = true but you will not find in a transfer and you are not able to accept it unless you create and finish a new transfer.
It took me hours to find out why I had products with incoming inventory while in fact there wasn't any incoming stock.