Theoretically there is not point to update the pi-star through SSH session, when you can just simply click Update in GUI:
However, sometimes you can get the update which is not officially released yet – like now (December 2021) when you click update the latest version is 4.1.5, also on Pi-Star website the latest version is 4.1.5, but when you go though SSH and type sudo pistar-upgrade, you get 4.1.6 version: