Announcement reposted from Amazon Japan:
Starting November 14, 2024, you will have the option to specify your preferred delivery instructions for your Multi-Channel Fulfillment (MCF) orders at the time of order creation. The feature will be available for orders created using the quick order form or through API. If no delivery instruction is chosen during order creation, the delivery preference will default to “unattended delivery–Front Door” as the preference. Delivery preferences are best effort and will be applied when possible.
For more details, visit Multi-Channel Fulfillment: Fulfill orders for your sales channels.