[cups] No duplex on Konica C364

[Bob Burton]

I have a couple of Konica C364 printers that have lost the ability to
perform duplex printing under cups.  Of course, I really don't know what
caused this, or when it occurred--it was just brought to my attention
today.  Duplex printing still works under Windows 10.

Has anyone else run into this?

-- 
Bob Burton
IT Support Analyst
Departments of Mathematics & Computer Science - University of Arizona
520-626-8203 -- bobburton at math.arizona.edu

The chief cause of problems is solutions.
—Richard Sennett