This is the planned change to Riflemen, posted 31st December - to my knowledge, hasn't been implemented yet.
Yup, we have only reduced the rifleman slots from 10 to 6 in one of our previous game updates.
I'd like to look into that when we're re-designing the class system. We need to integrate the new User Interface before we do that, however otherwise players will not know the difference between classes.
You can look at the developer blog series we released before the game was launched on Early Access for more on the re-design.