I don't believe it has anything to do with the dysphoria going up or down, rather that you are finally getting to be comfortable with yourself everywhere EXCEPT work, and because they don't know they have no idea that calling you sir bothers you. Until you come out to work it going to bug you as you do more life outside of work in your female persona. Just part of what comes with transition honey.
It happens to me to as well, except everyone at my office now knows I am in transition. And while I still go to work in boy-mode (not for much longer) I have noticed that my manager is starting to catch himself when he say "hey man" or something along those lines. All of them still use my male name as I've not yet requested that they switch, that will come when I start going to work in girl-mode. One of the woman in the office quietly says ma'am or miss to me every so often which is awesome tho.