Shorter Women's hair in Basic Training

I am going to Basic on the 28th of this month, and I wanted some pointers on hair if anyone can help. My hair is just above my shoulders, and I can get it into a very small ponytail, but everywhere I have seen says it needs to be in a bun or above the bottom edge of the collar. Since it is pretty close to where the collar should sit, I was wondering if I will have trouble? Will I be able to keep in in a ponytail or would it be best to get it cut shorter, about to my chin so that I can just smooth it back? It definitely won't fit into a bun. Thanks in advance!