Bleeding attack aircraft after update... (Battlefield 1)

I can't understand what happened with the bleeding attack since the last update ?I am a class rank that is on the attack can't raise 8 to 9 for quite some time although earlier this was not a problem ,if a sniper 2-3 fights and a new rank of the attack for 5 battles, and 5% experience not stuffed !Maybe I do not know about the leveling of this class ,in the sense that you need less people to kill and more equipment or I don't know what else but progress goes very slowly !Maybe someone knows some secrets, or bugs as quickly to reach at least to level 10 ?