The spec should never have been hitting through HP caps. That was a bug from when the crossbow originally released.
As for the hitting a tick later, this is due to the other fix to allow the bow to work with things like challenge gems etc etc.
It's a little complicated to explain and I didn't do the fix that causes the 1 tick delay but can explain it a little bit. Essentially, in order for the blight damage to run through our core combat system properly we need to add a 'fake npc' that applies damage to the target NPC which forces it to happen a tick later than intended.
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