Updating to forever the newest MediaVPs is a lot more time than you think especially if you haven't touched your said mod for a while now and had no remote idea whether they at all ran with the latest and shiniest.
First, you will have to run through the whole campaign(s) again, with debug builds. The more you have released, the more time it will take. Already, the thought of running through all those missions for the 192,684th time again just once more requires some dedication I wouldn't blame anyone for not having. Second, unless you're extremely lucky and everything works perfectly, you'll have to extract all the files and fix whatever stuff you've run into. Good for you if those are just little things like renaming subsystems or getting rid off unused-but-not-deleted weapons or ships from the tables. Chances are, over the years, the debug build you used for the old release became obsolote, and the new one will find errors you have no idea how to fix. Searching the forums then asking for advice if you can't find the solution you're looking for? Some might say this is ridiculous and stop there.
Assuming you fix all the errors the debugs complain about, and the many missions run through as a campaign from start to finish fine, you will inevitably run into stuff you want fixed/polished now that you've decided to revisit your old battlegrounds. A directive forever remaining incomplete here, cluttered messages, missions starting so abruptly it surprised even you as the maker of said mission, weird briefing icon placements, stupid messages here and there, unclear, confusing, or nonexistent recommendations in mission messages of debriefings. Oh, and WTF was I thinking when I released this mission with this difficulty? Have I forgotten to play or was the mission so ridiculously unbalanced in the first place? And the list goes on and on. Rinse and repeat for all the missions you're revising.