Yes, that is how my header looks.
I discovered one part of the problem…I had the Sort set to “Due Date”. Apparently that hides the Today and Upcoming Headers (but not the “Later”). Changing the Sort to “None” restored the Recently Assigned, Today, and Upcoming Headers.
However, I still have the issue of tasks newly assigned to be due on the date today (Mar 23) NOT moving from the Upcoming to Today header. Is that move something that can happen any time, or is just a 1-time early morning event?