I have found a couple cases lately where SEI_ENV was switching out of earthquake mode too quickly. Peakmon was still around 1000nm/s, fairly high, and SEI_ENV would switch back to the nominal state. During the winter, I had to increase this transition threshold from 600 to 1100 because the high microseism was fooling the SEI_ENV guardian. After that, I made an adjustment to the bandpass filter peakmon uses, to better filter out the microseism (here), but didn't reassess the SEI_ENV thresholds. I've set it back to 600 for now, I'll try to figure out if we can live with this threshold wrt the filter I installed in January.

This shouldn't really affect my alog about the earthquake robustness. This threshold affects the transition out of the earthquake mode, there is a separate threshold of 400nm/s for the transition into the eq mode with seismon early notifications, and we are mostly losing lock before even reaching that threshold.