How do I know when to re-extract and calc all the maps, vmaps and/or mmaps again? #31704

Is it as simple as "only on a minor version change" or will I need to do this every wow build update no version change?

Given all the previously extracted data upon initial setup, will the extractors and/or assemblers skip items that are and will be completely unchanged upon a subsequent update? Are the extractors saving any details on what work they've done, any hashes of the processed wow data such that we can see which files we have in our data folders and/or which things have changed and need re-processed? Or are the generated files merely the end-result work and none of the metadata we would need to optimize/skip a lot of unneeded and repeated work?

Maps and vmaps seems like "fine whatever, they don't take much time, maybe 20-30 minutes", so fully reprocessing isn't that big of a deal, but mmaps take longer than "just a couple of hours" like the wiki states (I assume it used to take that much time a while ago with less expansions under its belt) wiki

That aside, will I need to rinse and repeat after every minor update? If not, how do I learn to know when I will. And are all processes required in such a situation or can I re-extract maps/dbc/cams and generate vmaps skipping re-generating mmaps for a month or two or something like that.

Sorry peppering with the number of questions but I'm just trying to get any information I can since there isn't any on wiki for the kind of rolling updates master branch has, and I'm new.

Feel free to answer any, all, or none of my questions. Also feel free to answer any questions I didn't ask but should have.