I did a similar thing. Was at the point where I was very nearly ready for my test, and then didn't get around to arranging any lessons. A few weeks without lessons somehow turned in to over a year. Second time around, after my first lesson, my driving instructor booked me in for my test. That then gave me 6 weeks, where i did 2-4 hours a week.
If you were almost there, it should come back to you quite quickly. I would imagine that 6 hours a week practice for 6-8 weeks would be more than enough.