Why locking the angle dimension won't work -

- I need dimension to change with each configuration

- The dim value isn't changing during the flips.  If its value is 60 degrees before flip, the part visually goes around center point exactly 60 degrees.  After flip the dimension still says 60 degrees (so I believe lock won't work), but it's like it's reversed how it is attached to one of the lines and the resulting part goes around 240 degrees, meaning the dimension goes to a line colinear with the original line, however the line now shows 180 degrees around the center point.

I am not looking for a method to keep fixing this after every flip.  How do I prevent it from happening?

Thanks!!