Points to note

From this interface, you can cancel a sales order using the sales order number and/or dispatch number.

Non Wave Picking

Once a Sales Order has a status of "To Dispatch" it cannot be cancelled.
No matter which status the order is cancelled in, the DC will push the sales order through to Pick Complete status first before the sales order shows as cancelled on SupplyStream. See diagram for the systematic flow.
If stock has already been picked by the DC, an ASN is created: 'SS Cancellation - Dispatch {dispatch number}'. This will appear on the "Delivery List" Report.

Wave Picking

Cancellation Reasons

The highlighted field is the sales order number that had had a cancellation request created for it.