From the Chick-fil-A Facebook events page:
Like our waffle fries? Then, you’re REALLY going to love Friday, March 4.
An innovation in ketchup calls for a celebration. Between 2 and 4 pm local time, ketchup lovers who ask for Heinz Dip & Squeeze and the Free FryDay promotion at all Chick-fil-A restaurants will receive a FREE medium order of Chick-fil-A Waffle Potato Fries, limit one per customer.