Track a card's progress by adding a due date. By default, a card does not have a due date. Once the card is marked as complete, the due date will be replaced with a completed date.
From the mini card:
navigate to the Voice Page
hover over the card you would like to add a due date to
click on the 📅 calendar icon
select a date from the date selector
From the Expanded Card:
expand the card by clicking on it
click on the 📅 calendar icon on the top left
choose a date
If a date in the past is selected, the card will be marked as "overdue" until it is given a due date in the future or a completed date.
This functionality is the same on the Search Page as it is on the Voice Page