No, the island expansion should stay, as expansions are tied to physical coordinates, not players. If for some reason it doesn't, it can be added back to your island without having to purchase it again, as long as your physical location hasn't changed. If you trade islands with someone, however, the player that received your old island will then get the expansion.
But I know you can change your coords by joining another coop, someone else then does /newisland and gets my island, and when I do /newisland again, dO I lose it?
If your cords changed, yes. Michael explained that. If you leave your island with a current expansion to join a coop, and someone gets your island, then they now have the expansion you paid for.
I had this problem so I asked Lee. I bought a 199x199 for the wrong ALT, and he was able to transfer it. Maybe if you join a coop you can coop an alt so you don't lose it or maybe transfer it to the new coop you are joining?
Even though I was wondering too, on the NET server, If you reset your island while having 199x199 does the expansion stay?
Yes, the expansion is pinned to the island location. If you reset your island, it does not change the location of it.
Thank you for your thread on a recent issue. The issue has been resolved. This thread has been moved to the Help Archives.