Your account would be gone. It is one of the main reasons I’m looking at hosting my own private instance.

There’s currently no way to migrate accounts between lemmy instances. I know that this capability is one of the main feature requests, so hopefully the developers can add it at some point in the near future. Not only would it allow users to migrate if they have advanced warning that their instance will shut down, but it would make it easier to spread users out amongst the federated instances to avoid there being only a few “main” instances.