@Glenn
The scuttlebutt around this, briefly, is that Ash is Voq, so the whole thing about him being on the ship 7 months is a lie. Last episode, L'Rell told Voq that he would have to "give up everything", and since he has no family, no ship, no mentor and no followers, all he has left is to "remain Klingon!". With need to reconcile Klingon appearance with canon, one can theorise that Voq gets turned human-ish in order to infiltrate the Federation, either surgically (has precedent) or through the augment virus. There's also precedent for accelerated learning to explain his language skills. The Klingons knew where Lorca was going to be so you have to assume they have someone on the inside already.
It's all over TrekBBS, Reddit etc, lots of people explain it in more detail.
Regarding Klingon Captain being female, here's a couple of screen caps I took from episodes 4 and 5, looks like the same character to me!