During the Abomination fight, I destroyed all 4 Soul Vessels and the blinking indicators for all 4 areas of the map had ceased to appear. The boss was still not taking damage, then approximately 30 seconds later the Soul Vessel in the south east corner reappeared and began blinking on the map (it had approximately 25% health).
I’m not sure if this is a random occurrence or a function of the way in which I killed the Soul Vessel (I was using Lunge/Vengeance/Abyssal Echoes) or how you would recreate it, but I thought I’d mention it so the devs could keep an eye out.