I got a similar question but didn't want to start a seperate thread.
I emailed COFA and they told me
"If you complete at least one year's worth of full-time study in a University program then the UAC can calculate a new UAI for you based on those results. When you apply for any new programs, you will automatically be assessed on whichever of your two UAIs is higher - your high school UAI or your new UAI. However, if you do receive a new UAI from University study, then your High School UAI will only be valid for three years after the date you finished high school"
So..right now my UAI is higher than the program i want transfer to by a couple of points, if i only complete 1 semester of uni and completely fail, and take leave in semester 2, would that 1 semester which i fail in, affect my chances of getting accepted into the other program. According to COFA's reply it shouldn't, but im not sure, wanna see what more people think.