Acrobat DC - Slow exporting to Postscript

Hi Guys,
I've been struggling with an issue that is plaguing our work team at the moment, although it only seems to affect people other than myself. We have a variety of different machines, although at one stage where we were using identical spec'd machines they were exhibiting the same issue.

As part of our workflow, we use another software product (Nitro) to combine large numbers of documents (including .msg files, .doc, .txt, excel etc) into a PDF. For reasons that I'll explain, we then use Acrobat to export to a Postscript, which is then run through Distiller. These resultant PDFs can be anywhere from 100-5000 pages.

When other people export documents to .PS, they find that the process takes an extraordinarily long time. Often the most time consuming part is the 'flattening' stages.

The reason why we have 'always' done this postscripting is that we use a plugin called Redax to redact information from these PDFs. We have found that if they are not postscripted, this causes problems with the redaction process where it will redact unrelated portions of pages. 

My PC is running Windows 10, Adobe Acrobat DC v2020.013.20074
PC Specs are Intel I5-6500 @ 3.2
8gb of RAM

Thanks
Dave