A "senior medical officer" is a consultant-level doctor. People move around all the time for training purposes - the soonest you could easily move, as I said before, is from PGY3 onwards. PGY2 jobs are largely accounted for in NSW, so you would have limited options there.
As per the beginning of this thread, outsiders being offered PGY1 positions is possible but certainly not guaranteed. The context of the current discussion is about the point at which it becomes easiest to secure employment as an outside applicant - which is not straight after graduation.