The MerchantFulfillmentOrderId must be unique for all fulfillment
orders created by the merchant. If your system already has a unique
order identifier, then that may be a good value to put in this
field.

This DisplayableOrderDate will appear as the "order date" in
recipient-facing materials such as the packing slip. The
DisplayableOrderId will appear as the "order id" in those
materials, and the DisplayableOrderComment will appear as well.

The ReceivedDate indicates when Amazon received the
CreateFulfillmentOrder request for this order.

The StatusUpdatedDate indicates when Status of this order last
changed.

ShippingSpeedCategory is the Service Level Agreement for how long it will
take a shipment to be transported from the fulfillment center to
the recipient, once shipped. The following shipping speeds are
available for US domestic:
Standard: 3-5 business days
Expedited: 2 business days
Priority: 1 business day

Shipping speeds may vary elsewhere. Please consult your merchant
manual for published SLAs.

Status of a fulfillment order. Described by the following states:
New: The order has been received but not validated.
Received: Validation is complete but no action has been taken to
fulfill the order.
Planning: The order has been sent to Amazon's fulfillment network
but no shipments are currently being worked on.
Processing: At least one shipment is currently being worked on.
Cancelled: The order has been cancelled by the merchant.
Complete: All items on the order have been fulfilled.
CompletePartialled: Some item-quantities on the order were
fulfilled; the rest were cancelled or unfulfillable.
Unfulfillable: No items on the order could be fulfilled.
Invalid: The order was deemed to be invalid and no further action
can be taken.

Postal address. CountryCode must be the ISO-366 alpha-2
code (example 'US', 'UK', 'CA').