It's usually convenient to have Gig Performer load the last gig file automatically at startup and there's a general option you can check for this to be the default. However, occasionally you may need to temporarily prevent automatic loading. One reason is because you do want to load a different gig file and don't want to have to wait for the previous gig file to load. Another common reason is because you want to change your sample buffer size or sample rate and this can be done much faster if no rackspaces are loaded.
To prevent Gig Performer from loading the last gig, please follow the guidelines from this article: https://gigperformer.com/how-to-stop-gig-performer-from-automatically-loading-the-last-gig-file/