line magnetic 805ia and cossor 805 tube

Can someone with the same ''problem'' please help me ??!!
I have just bought a pair of cossor 805 tubes as upgrade for my line magnetic 805ia amplifier.
with  this tubes comes the data/cart sheet ,and there begins the problem, 
on this data sheet it states that the plate current for the cossor 805 is from 65 ma.
the Original tubes are biased at 120ma,....
I do find a big difference here , 
my question is : is this normal ? because to me 65ma it looks more like grid current.
should i biased the cossor 805 at 65 ma ?
maybe someone here with the same combo ??