The big problem for me is editing the pdf file. Most of my work is hugely graphical with text boxes. Some has gobs of links that, when the text changes, the links are on another layer and must be moved to match, especially if I insert pages and the internal reference links must point to the correct pages.
The way I update the files is to print a file without links, and slide that text layer under the links as a "replace pages," else I have to make thousands of them one at a time. If there are new pages, I make dummies in the new revision before executing the layer replacement. So far, I haven't do that type of doument maintainance in Linux pdf variants.
Sorry--I was just picturing a final version in PDF. I had not thought about editing them.
There are several PDF editors for Linux, though. I'd recommend importing the source .docx file into LibreOffice and see if it saves correctly (Not all docx files do). If it does, then moving over to Linux should be simpler.
One more question—why edit the PDF at all if you have the source document? Just edit the source, and re-export it out to PDF.