To unlist SKUs on Target please reach out to our support team with a full list of SKUs you would like to unlist in a CSV format. Our team can then handle the deleting of SKUs on Target's side.
When you unlist a SKU on Target it will take the item down permanently along with all of the data on that listing. If you wish to sell this item again, you will need to relist it in Zentail to initiate a new listing getting created. It shouldn't take additional work to get the item listed because all of the data in Zentail has not changed as long as the requirements have not changed on Target.
You may find the need to unlist SKUs on Target due to maintaining your out of stock rate as well as keeping under listing limits!