No it's not gone, and it is not a gpsapp problem. There are some cases where hijack 'forgets' there is a userland application running. My guess is that the application restarts, or hijack tries to popup some message and the redirections are removed.

You'll notice that whenever you enter the hijack menu, gpsapp 'ghosts' through for a second, it is still running fine and trying to update the screen and listen for buttonpresses that are not redirected anymore.