Right now, if you navigate to a "Due date" field in a Work Item that has no value and set it up to recur (such as daily or weekly), this is allowed.

Logically, it is unclear what "recurring" an empty date will do.

What it actually does is create a read-only Automation rule in the background to clone the Work Item in regular intervals.

After setting up the recurring "Due date" that had no value initially, the UI does not indicate that the "Due date" is recurring or doing anything, from the Work Item screen (unless you click to expand the field value).

ie. look at the Work Item and see that "Due date" is set to None. There is no indication that there is actually an active "Recur" set and an Automation rule running (which by default will run for an entire year).