I simply ignore everything new, except for the few bitz that i do like, for instance New Newcrons. My headcanon 40k is still stuck in M41.999. Primaris never happened, Cicatrix Maledictum never happened, Abaddon is still bashing his head against the Gate of Cadia and did most certainly NOT waste a Blackstone Fortress etc pp there's too much newfangled garbage to keep track of.
I simply ignore everything new, except for the few bitz that i do like, for instance New Newcrons. My headcanon 40k is still stuck in M41.999. Primaris never happened, Cicatrix Maledictum never happened, Abaddon is still bashing his head against the Gate of Cadia and did most certainly NOT waste a Blackstone Fortress etc pp there's too much newfangled garbage to keep track of.