I think height should be factored into this. I did SL to APL in 10 months.
But I'm 5'8 1/2 and my hair grows a half an inch a month.
Someone shorter (esp with a faster growth rate) could do it sooner
Someone taller with the same growth rate could take longer
etc, etc, etc
but yeah it's possible cause I did it
I'm also 5'8.5 & that I believe that height also plays a factor. Right now my hair is about 12" & I just made to apl but to be full apl especially in the front & crown I'll need to grow about 4-6 (maybe). The sides are are almost there (i have a big head & proud of it
)
You can get there w/ patience.