I do 1hr of phys, 1hr of chem, 1 hr of MX1, and 1hr of MX2 each night.
Thats roughly speaking, I judge tasks by length to be an hour and usually am right within 5 minutes. And yes you read correct, I dont do english on a regular basis. I rote essays n creatives the night before lol.
They say for 99.95 it is best to do 4hrs a weekday and iirc 10 each weekend day, with over half that time on english. Ive heard literally 5 or more 99.95'ers tell me that english takes up over half their time.
So for an ATAR in the 90's I am guessing 90-120 mins a night would do it, 99+ is about 3 hrs perhaps, idk.