PS5 Lich Health Reservation/Boss Stuns

Hi,

I am not sure if the first one's a bug (yet), however, I do encounter an interesting behaviour.
1) HP bar constantly at 50%:
I have both ES and health, when a mob hits me through ES and HP bar gets low - after recharge of the ES the HP bar remains on the same level.
Using the fountain set the HP back to full for a brief moment - and then it goes down again.
Seems fixed after getting low enough (to about 10% HP) and healing from there.

2) Stun animation on bosses.
Plain - when the stun bar fills and the boss goes into the 'stun lock animation':
a) You don't do damage because where the model is not where the actual boss is.
b) When the stun bar depletes and the boss should be standing up - there's a brief moment where the boss cannot be seen but is performing actions. Got killed a couple times because what I am seeing is both is stunned, but in reality it recovered and is actively hitting me with invisible attacks.