How do equipment buffs work on towers when switching characters?

I know from this question that when switching characters, the active character gets all the experience and credit.

However, how does this work with gear-based stats buffs? Does the tower get the weapon/armor buffs when it was placed, or from the current active player?

Example: I have a Squire with +20 to Tower Damage from buffs on his gear. I place my towers with him, then switch out to my Huntress, who has only +5 to Tower Damage from her gear. Do my towers get +20 damage or +5?

My main concern about this is because in using separate characters for Towers/Hero DPS, I often have gear that is tailored very differently. For example, on my Hero DPS Huntress, I may ignore the fact that a Bow has -5 to Tower Damage because I'm only using her for DPS. I don't want to accidentally nerf my towers though.

The equipment on the tower placing character is the equipment that matters for the defence built, so the towers would get the +20.

However, the active character's defences get a 33% boost, as noted by Patch 7.11 (scroll down to read it)

PvE: Active (non-retired) Heroes boost boost the Damage output of towers they specifically summoned by 33% (indicated via a Hero Face Icon on the tower's floating HUD)

(So when you switch away from the tower builder you are still nerfing your towers a little.)