Sorry to bump,but to elaborate, physical dependency takes a certain amount of time to develop, once you get to that point of being physically dependent, your dependent, period. Regardless of how long you have been dependent after you reach that point, it won't make a signficant difference in withdrawl, since your already at that key stage anyway. Focus more on the daily dose you take, and acknowledge you are physically dependent , so you can voice your concerns to your doctor, or keep in mind medical attention is a possibility coming off of it.
Like I said, .5mg is not anything to be worrying sick over. I was prescribed klonopin for 8 yrs, and was on .5mg twice a day, my doctor dropped me down to .5 once a day, and that was it, nope , nada, no .25 decrease. It WAS very uncomfortable to withdrawl, however I was in no danger of a seizure, and according to my doctor (i wanna note, that my doctor is an M.D., his credentials go beyond blue light) and he told me I will be fine stopping at .5mg, he mentioned it may be uncomfortable, but fatal or risks of seizures, no. Then again my human body is different than other people's human bodies, so idk if anyone has ever had a seizure from .5....I suppose it's possible tho