Everything is possible.
It's all down to determination and how much you want the reward. Some will need to show more determination than others to achieve the same result, that's like everything in life.
Give up work, live like a hermit and use a structured plan and I'm sure it would be possible to pass them all in under six months. If that's not viable assess your own abilities and come up with a plan that will work for you. That's the easy bit. Now all you'll have to do is dig deep and show that determination. Nothing worth having is easy to attain.
Sleeves up, heads down, and good luck!
PP