The best thing you can do right now is self-learn. If you can't self-learn, going to uni will be hard because they expect you to be able to work independently. When you get to uni or tafe you'll see a lot of people who already have some programming skills from just fooling around with code...
If they advised you to complete it, it means that they expect that you understand the concepts of those subjects, and you won't struggle at college when they move onto harder topics.
I didn't go to my formal and I had no regrets.
Nearly everyone will tell you to go to formal though because they all want to, and they can't understand that some people don't.
Official release is on the 15th.
Provisional maths marks have been released (at least they are for 1131 and 1081): https://portal.maths.unsw.edu.au/index.php