Getting to low suppression resistence (ugly word, seriously, call this "armor" or something -.-),
or getting hit by a mine, and some other things,
will remove all your non-permanent buffs.
This is probably "new" as only the psyker has a lot of buffs to cast, but it is not only annoying but also apparently not thought through.
Simple: Death Augury, this buff would help you in case you're near death, but this wont help at all as if you're near death, especially suddenly, you are also likely low on suppression resistence (seriously, give this a good name, it does not get better with time),
which means in 95% of all cases you will be debuffed and the whole thing is totally pointless.