POE 2 Witchhunter: Sorcery ward not reloading

I dont know if this is a bug or only a very annoying feature, but my Witchhunter ascendacy "Sorcery Ward" is never reloading due to constant changes in my own eva/armour values.

I play a Crossbow build with a lot of different ammunition and make heavy use of the two weapon sets, constantly switching between them in combat.
One set has more increased eva/armour, furthermore I run Wind dancer which changes my eva when hit, there is the node with 120% increased stuff while on low life, maybe even a node with benefits on full life and so my def values change all the time.

Now I run sorcery ward, which should restore its value after not taking damage or being depleted, which is indivated by a countdown. However, every time my deffs change and with that the maximum value of the sorcery ward health, the countdown is reset to the full time.

This feels wirse than energy shield on level 1 characters, as you don't only have to be out of combat for several seconds, but furthermore one wrong button press screws you over again.

Is this a bug or such a bad feature, that I should completely spec out of this useless skill?
Give some love to builds that are not glass cannon and 1 button only.