Thanks for this, I think you are right.

A near identical installation on the production system didn't show this problem, and when I updated the firebirdsql python package on the test system the problem resolved.

The database is primarily used as the backend for a niche commercial radiation measurement application which is rarely updated, so upgrading the database isn't really an option. My access to the database was just to hack the data and redirect it to a preferred data repository.But I appreciate the suggestion

Gary