Ahh thank you for your information. I tried using that idea by sitting outside brisbane until when it supposedly is meant to be offered there (according to information I found on the sh4 fandom page). However that failed too.
Unfortunately, once I return from a patrol I delete the various saves I made that patrol, and the autosave from port entry us from after I accepted the upgrade, leaving me with no alternative but to give up on a career I've put 75 hours into

* if anyone else has any other suggestions please do let me know because I want to avoid having to do this at all costs.