It does, more than you might think. March 13 was a Monday. Normal lockdown would be on Friday March 31. One day early would be Thursday March 30. I think you made a very common mistake.
An egg does not have a day's worth of development the instant it goes into the incubator. It takes 24 hours for the egg to develop a day's worth. So when you count you say "one" the day after you put them in the incubator. One way to check your counting is the day of the week you start them is the day of the week the 21 days is up. In your case that would be Monday April 3.
Lots of people make that mistake, it is a common reason hatches are thought to be late. But even when locking down a day early, most people still get good hatches. You want to do everything right but there is some wiggle room in a lot of this. Just do the best you can.