Must the OS be upgraded on IIX server to install DocuWare v7.9?

If IIX is already installed on Windows 2016, must the OS be upgraded to 2019 to install DocuWare v7.9? DocuWare Help states 2019 is a requirement for IIX as a local installation. This is IIX v1.

Dear Mark Massey! It looks like the Community cannot answer your question. That's why we have opened a Support Request with the Number SR-215055-Z1W1P for you. A Software Support Specialist will contact you directly to follow up. We will update this thread with the solution as soon as we have resolved the Support Request. With best regards, DocuWare Support Team