Not trying to be a dick or anything but this is not entirely true.
you cannnot transplant acacia plants beyond a certain age. it will mean certain death for your plant im afraid.
Ive never tried this with phleb but most acacia's can be transplanted or repotted year after year. You just need to get the timing right.
You have to wait until the the first flush of growth for the season has matured but before the buds burst for the second flush of growth.
Between these two flushes of growth most natives go into a semi dormant state. They do this to combat australias hot summers and drought conditions.