No. That 477 would have scaled down to something lower. This is because everything scales down (check out the scaling tables)
Where did you get that stat?
ATAR is calculated using scaled aggregates. Last year, the lowest scaled aggregate for 99.95 was 476.2, this year, it is 476.5.
Because of this, you can't use the aggregate of HSC marks as a means of determining ATAR. Now keeping in mind that pretty much every single subject scales down, an...