I have same issue man, I even submitted a ticket.. still no reply from them Just my issue is a bit different, my sea claim overlapped my land - which allowed people to build on it. Even when I did copy settings on land it did not do it for sea (apparently they need to be set separate?) I've waited all the time needed for demolish to be allowed , even for storage boxes. They are demolishable now too.
The leftover junk all over my land is blocking many spots that have important resource nodes. Sigh. Then people wonder why some people hog the land and just don't want any random people building on it.. when these trolls and people that leave the leftovers of their traps etc, don't clean up after themselves..
I really hope they fix this, it has been probably two weeks now that the junk is still in my land..