1.5.5: Pedestals/statues reset - infinite Bringer of Dooms

[Sinister Stairs]

I am playing 1.5.5 (OS X) and I have the Bringer of Doom pedestals in Old Forest (1), and a Statue of a Fire Imp on (3). After activating the pedestals / killing the summons and Bringer of Doom: Whenever I leave the zone or save/exit game and return, two of the pedestals reset (can be activated again) and another Bringer can summoned / farmed for rare treasures.

The Statue of a Fire Imp similarly resets and can be re-activated when I leave the zone or save/exit and return, although thus far I've only gotten one rare drop from it -- maybe just bad luck.

Unrelated, please set up HTTPS for the forum login/password. https://letsencrypt.org/

[Sinister Stairs]

I just spawned 3 more pedestals in Tempest Peak, and these did not reset when I left the zone and returned.

I cleared all 3 pedestals in Tempest Peak before I left the zone (i.e. killed the Bringer of Doom); while I believe with Old Forest I left the zone after clearing 1, before the Bringer.

After verifying my Tempest Peak pedestals remained (post-)activated after leaving the zone or saving/exiting; I confirmed that I can continue resetting my Old Forest pedestals and re-summoning the Bringer by killing him, then leaving the zone and/or saving/exiting.