The minimum aggregate for 99.95 usually sits at just under 480. Assuming you achieved perfect 50/50 scaled marks in every other subjects (basically means you need to state rank a bunch of high scaling subjects), this means that you need to get 80 scaled marks from English (or 40 per unit). According to the 2020 scaling report, this is an English hsc mark of around 44 per unit, which means that you would need a hsc English mark of 88 — obviously this is purely hypothetical and unrealistic, and in the real world you’d need to perform better than that to account for imperfect performance in other subjects.