Hi Edward, you'll need to give a lot more specifics about yourself for anyone to hazard even a remotely accurate guess of timeline!

As Harry mentioned, the time someone takes to prepare for PMP varies widely based on so many factors:
1. Are you an experienced PM professional, familiar with ways of working?
2. How quickly you grasp the "PM-language"
3. What age/stage of life at you at - working parents often have many pre-existing commitments, so carving out study time can be much more difficult than for single/ childfree folks.
And so on..
Best of luck to you!