2 for the price of 1

I too have had the pleasure of the Jetstar curse.
Mid year I bought 2 tickets for the price of 1, using my Club Jetstar account and paying for them using my credit card.
In early October, Jetstar Australia had a sale on during my flying period for next year, so I decided to upgrade my ticket for return leg to business class. I tried to upgrade on there website, which couldn't be done, so up popped up Jess, and she said to call the number that she provided.
I then called the number, and to my surprise, I got a Pilipino call desk. I calmly explained that I wished to upgrade for the return leg home.
Lo and behold, I was told that I cannot upgrade due to the fine print, I was the free passenger nominated for that special deal. I explained to the call centre operator that when booking the ticket using my Club Jetstar account, it auto filled my information as the free passenger and which then I nominated passenger 2.
I asked for the information to be changed and all I got was sorry sir we cannot do this. At this stage, I asked to speak to the supervisor, and you guessed it, "sorry sir, you should have read the fine print" As I explained to operator 1, it auto filled my information. The supervisor had the same response as to operator 1. ( THE MUST HAVE CHEAT SHEETS ).
On the Australian Jetstar website, the upgrade was advertised for $467.00 for the return leg, which after consideration, I was willing to pay for it. After accepting their robotic reply's, I asked to upgrade my flight, she then said the ticket would now cost $763.00 as they did not have access to the Australian Jetstar website.
I then asked her to stop and asked for an Australian call centre contact as I wished to lodge a complaint, but all I got was there scripted "sorry sir". By this stage, I was fuming. I have used this company on 8 occasions in last 2 years on International routes. I know that this airline is a budget airline as I chose to support it being a Australian product, but I would like to know why I have to deal with overseas operators when I made a deal with Jetstar Australia which auto-filled my information, yet I had to deal with Jetstar Asia with there scripted responses?
After this upcoming flight, this will be last time I will use this carrier, the Club Jetstar account has been de-activated and I managed to convince my boss to change the carrier.

Australia-Melbourne - Tullamarine