Same Day handling time allows you to show the customer a faster delivery promise that reflects your ability to pick, pack, and ship a product the same day of receiving an order. This only applies only if the order is received before the cut-off time.
The feature is only available to sellers that meet high delivery performance standards.
Requirements for Same-Day handling time:
The default order cutoff times for your Standard Shipping (when Same Day Handling Time is enabled) orders is set to 2:00 p.m. local time (as per the time zone of your default shipping address).