Me and my partner (who is genderqueer) have a really strange kind of dynamic in that we do switch, but in the bedroom ze tends to be more dominant (technically - i often sort of direct things, or top from the bottom, so to speak), whereas in other aspects of our relationship I'm distinctly in charge.
We share everything, but when switches happen, it's complete. They also are prone to happen literally in the middle of having sex sometimes.
Oh, and I'm male. Forgot to mention that.
Overall, I'm the more dominant one in our relationship I think, but I get off on being the sub just as my partner enjoys domming me periodically. So we're fortunate in each other's preferences being so in tuned to the other, hehe.