Question About Long Duration Spell Damage Mechanics

If I cast a longer duration spell like

Armageddon,

Hurricane, Blizzard, etc and swap to a weapon/shield with -enemy resistance, does the spell factor -enemy resistance into damage going forward, or does it only apply damage based on the original environment in which it was cast?

Thanks.

As with magic find, the game instantly updates status effects upon gear switches. It's even true for individual projectiles. I.e. if you cast a

Fireball while wielding a Phoenix shield and swap over to your CTA + Spirit while it's in the air, upon impact with the monster, the

Fireball will deal damage unaffected by Phoenix.