As you might know, Target Plus has a number of requirements to sell on Target, especially around shipping. You'll need to be prepared to ship out orders within 24 hours of receiving the order (contingent on your shipping hours which you can configure in the Target portal), and have a max 5 day transit time.

One other major requirement around shipping is making sure to use a compliant carrier and shipping method. This is the current list of allowed carriers and shipping methods: