Is there a name for a non-ambiguous statement that contains unresolved ambiguous details?

Yearless dates can be ambiguous. "04/07" for instance is understood as "April 7" by Americans, but as "the 4^th of July" by most other nationalities.
This ambiguity is frequently resolved by the context it was written in, but often not.

I recently wrote something using this date format, saw that it would be ambiguous, and then immediately realized that it didn’t matter.
The two dates were individually ambiguous, but together they weren’t:

Each year, 05/09 and 09/05 fall on the same weekday.

It doesn’t matter whether one reads these as MM/DD or as DD/MM; the sentence is equally correct, even though the two dates each remain ambiguous.

Is there a name for this phenomenon of ambiguous details that together produce a non-ambiguous result?