Since GhostBSD ports are derived from FreeBSD ports, you can check whether a particular package has been updated upstream by searching for it on FreshPorts.
If the latest version of Fish isn’t listed there, it likely hasn’t been committed to the FreeBSD ports tree yet — in that case, you can contact the maintainer (asomers@FreeBSD.org).
It seems GhostBSD updates its ports at least quarterly and sometimes monthly depending on development or security needs.
