Structure Set Question

I am creating custom structure sets for my modpack, like overworld, overworld_rare, ocean, ocean_rare, etc. My question is when I create a structure set and put a structure from a mod in it, what happens to the original structure set? Here's a more direct example. I install when dungeons arise. I create a custom structure set under a new datapack tutorialset/worldgen/structure_set/tutorial_set.json In this structure set I add all the structures from when dungeons arise except 1. These have new weights and a new separation / spacing values than the origina structure set. Does this completely overwrite the structure configurations from the previous set? What happens to the one that I didn't bring over that still only exists in the old structure set? Does it still exist in that set and the rules from that set apply to it?