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

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 DisplayableOrderDateTime will appear as the "order date" in
recipient-facing materials such as the packing slip. The format
must be based on the RFC3339 profile of ISO8610 as follows:
[YYYY]-[MM]-[DD]T[HH]:[MM]:[SS][TZ]

The DisplayableOrderId will appear as the "order id" in those
materials, and the DisplayableOrderComment will appear as well.

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.