I have a hair follicle test in a month. I haven't smoked in 6 mo and have shaved my head 8 times will i p?

Ive heard that if i were to let my hair grow and cut it it would be good so ive let it grow and shaved my head 8-10 times and within the past 2 months ive been letting it grow i have about a lil more than an inch now? andy suggestions anyone?