How to duplex with pdfPrint function

The TWPViewPDF supports duplexing requests per:

eg CommandEx(COMPDF_SelectDuplexMode, 2);

BUT there is no specific option parameter to set DUPLEX state
for pdfPrint function....

Is it possible (or can it be made possible) to set duplexing mode for pdfPrint?

Thanks.

Not meaning to be too impatient, but is there any timing available for release of this update?

(We're hanging out for explicit control of duplexing with print jobs...)

Thanks.