How does damage of lingering effects work with weapon sets?

So i have spell damage and extra damage modifiers on a staff on weapon set 1, which i switch to just to drop thunderstorm, thrashing vines and tornado after 8 seconds of being a furry, i also get spell damage from arcane surge modifiers, from passives on weapon set 1.

Once i shapeshift into a furry, do lingering spells retain the spell damage modifiers present when they were cast, or do they lose them in the middle of their duration?

The buffs are locked in when casting the spell.

You should also use you weapon set points to boost the damage and playstyle of each weapon to get maximum effect.