We don't have more than 4 people to test with, but I assume this linear progression keeps ramping up.
My friend only has 1.4 megabits on a good day. which means that when we are playing in a group of 4, he cant play with us.
1.6 mbits is roughly 700mb for a 1 hour session of dayz, if you have bandwidth caps, this is a big issue.
We only noticed this bug, recently but we dont know when it was introduced since we dont always play 4 of us together.