From my understanding the policy for transgender protections are going to be enforced 27 May 2016.
I'm sorry you are going through a hard time. It is a real big struggle for me too. Though I haven't come out to my command just yet I know its about a 50/50 chance I may be able to do anything.
Of course as the whole policies haven't changed yet, they may consider something later when the policies are there, but otherwise you will have to stick with the possibility of having a wig, nail polish etc... For off duty time, but on duty will of course have to be male mode for sure. Actually in reality if you use clear coat with a matte finish you could still paint your nails on duty time, but otherwise it'll be a bigger struggle.
I hope they can find a way to accommodate your needs if at all possible once it gets closer to policy changeover. Either that or you may need to consider, if it may be possible to transfer to another unit.
Hang in there, it always seems to get harder before everything works out.
Kate <3