If from the one order Product A took 2 days to deliver and Product B took 5 then the earliest delivery date is 5 days (in addition to any holidays/excluded days like weekends etc).
Magento 2 Delivery Instructions and Delivery Date extension allows customers to enter "delivery instructions" or "order comments", "delivery date" and "delivery time" during checkout, this information gets saved against order which can be viewed in Magento admin panel under delivery instruction section.
The following link Delivery Date and Instructions would be useful
Delivery Date & Time for Magento 2 allows the customers to choose their preferred date and time for their orders.
Once you integrate Appjetty's Magento 2 Delivery date extension, it takes all the speculation out of the order delivery process. As an owner of your extension, you can display the available order delivery dates and your customers can choose the one most convenient to them.
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