Does subclass stop leveling up at 55?

Hunter is leveled off there and 985,500 xp to go hasn't moved

it is 20 below main cap you can switch it to your main and level it more then switch back to normal anytime at the class counter (when I get XP tickets I switch use them then switch it back)

Yes, sub-classes don't go higher than a certain amount. You'll have to switch to them as a main class and turn in COs/etc. as them.

That's what I figured. Thank you!