Estimated Delivery Date (EDD)

The Estimated Delivery Date that the customer sees is now December 30 to December 31
My Handling time is 1-2 days and my transit time is 2-3 days so that should be 5 days maximum or 7 days maximum including the weekend
So it should be no later than a week today = December 19th to December 21st
Has anyone else noticed this and have a solution so the customer sees that it is delivered before christmas