Is actually not true.
Maybe, but probably not at Archerfield. Certainly my insurer would be most upset.
It would still save him $300+ for the check-ride by sticking with the flying school who gave him the PPL. I am sure he would also receive some valuable informal advice from his previous instructors who took an interest in him and know his skills. A review of his first few flight plans would be worthwhile as well.
All of this add-on service for just sticking with the people he was with.