Grid size

I have been modding on the Island Map, going well if I might say so ;), I would like to extend my grid within the existing template; is that possible?
Or is it possible to copy&paste an existing project onto a new (bigger) grid?

What do you mean by “grid?” The landscape?

Yes.

Pardon me for using that name, but I am customed to to that name when I modded other games in the past.
Sometimes I keep falling back to that instead of using the UE4 names.