How long does the program take?
The usual length of the program is four to six weeks. Why does it take as long as this?
Because you do not change a habit that has been entrenched for months or years in a
week or two. In particular, once your body clock has been disturbed, it takes a while
for it to be set right again. The longer the disturbance has lasted, the longer it takes
to put the body clock right.