Amazon shipments
Why is my purchase order split into two shipment plans when syncing with Amazon Seller Central?
If you create one purchase order or warehouse transfer in Inventory Planner and sync the information to your Amazon Seller Central account, you may sometimes find that two shipment plans are created - the single purchase order or transfer has been split by Amazon (with the split reflected in Inventory Planner).
To learn more about why this happens, see this Amazon seller forum.
This can sometimes be addressed in Inventory Planner by setting your UOM (units of measure).