Jos Dingjan@Aaron_DeVries @swope A lot of physical processes are thermally activated. At higher temperatures the barrier between two (meta)stable states is often easier to cross, which is why things can go wrong at higher temperature.
If it is, as I read it, bits _written_ at higher temperature having a shorter lifetime even at lower temperature after, I can imagine that the state written at higher temp isn’t as far down into the local energy minimum.