Hi Insomniac,
I'm familiar with the term. All you need is sim training for the left seat not unless it was already a part of your initial training before. In the A320 it is 30left / 30 right for PIC and CP rating. So, you will probably be looking at around 15-30 hrs in the sim for the left seat and maybe a pre-determined ICUS time as a training captain in the left seat in actual flight with a company designated TRI.
In regards to license, I don't think license is an issue with CASA if you have at least a PPL. I've seen PPL holders in the U.S. with a B737 rating in their licenses. However, it will be a company requirement for you to have an ATPL before you get left seat if you are in an airline or corporate flying to state the obvious.
cheers
