August 31 is the last day on which you can create shipments using the Send/replenish inventory workflow. Starting September 1, all new FBA shipments must be created either in Send to Amazon, or through Amazon Marketplace Web Service API or Selling Partner API.
Shipments that were created through Send/replenish inventory can be viewed and edited until November 29, 2022.
If you created a shipment in Send/replenish inventory before September 1, 2022, you can still view the shipment details in your Shipping Queue. The details include tracking and reconciliation information.
With Send to Amazon, you can create reusable case-pack templates to save box content information and prep and labelling details for shipments of single-SKU boxes. In addition, you can add both single-SKU and mixed-SKU boxes to the same workflow. For more information on the features, go to Create shipments with Send to Amazon.
The replacement of Send/replenish inventory with Send to Amazon won't affect Amazon Marketplace Web Service API or Selling Partner API. You can continue to access details and make changes to shipments that you create with APIs from your Shipping Queue after September 1.
At this time, you cannot view and edit shipments that you create with APIs in Send to Amazon. In the coming months, Send to Amazon will be compatible with the APIs. You will then be able to view and edit shipments that you create with APIs in Send to Amazon, or use the APIs to edit shipments that you create in Send to Amazon.