In 1.14.2 It seems to be whenever I expand a map using a cartography table it resets any charted area, and remaps the area I am currently in once done with the table. I was trying to expand the view of my map board and now will have to rechart those areas with pre-expanded empty maps it seems. Which is a pain in the rear if that's intentional.

Now tested in 1.14.3: it keeps the location of where the map was filled, but wipes previously charted area