Originally posted by Mharr:

In answer to the main question, no. The game will not regenerate any lands you've already visited and there's a huge safety margin on that, 500m radius I think? There's actually a popular mod to pull this distance in tighter and selectively recreate some world features so new regions actually have a chance to spawn in older saves.

thank you much, that is the info that i'm looking for. I have a few bases around but i really care about my big "main" base thats sitting in the meadows right now. I don't want them to delete that or my stuff in the chests. I would say about 80% of the world is still unexplored for me.