Obviously your medics will be the best people to guide you. Is the doubling time still 3 or 4 years or has it accelerated? You could consider holding off HT for a few more years. That would come with some risks. ChrisJ held off for ages until his PSA was around 1000.
You're going to have to find a way of balancing quality Vs quantity of life.
As francij says, this would have better been treated when it crossed 0.2 rather than 2.4, but you do have the advantage of having 15 years of life behind you without any worries.