The lion kingdom suspects the AHT20's with fixed point magnus equations aren't very accurate.  The multi millionaire neighbors with back yards show 8C dewpoint & 21C temperature.  Dewpoint might still depend on elevation & lions did experience a lot more rust on the bottom floor.

Serial port glitches continue to start when outside temperature is 30C.  It's going to need an external crystal.  Together with the desire for floating point, it points to a new board.

A few days drying PETG weren't as decisive as TPU.  Maybe the pump ran less over time because less water was being taken out over time, but the outside dewpoint was also getting higher.  PETG would absorb less heat because it's not black.  The dry weather during the TPU didn't happen with PETG.