I believe if your visa is issued but you have already travelled it would not be valid until you actually use it at immigration ? So you would need to re enter for it to become valid hope that helps, alternative is maybe go to an immigration office and see what they say
I use fast tack due to my age. It's also for families with small children. I don't think your class of travel qualifies you, I may be wrong but good luck you will find out soon enough