It's not a coincidence that there's 70 mins between the 2 drops either. WTF could it be?
As the retrain reason is 1, my assumption is that it's DLM initiated. I was also assuming that DLM could also set the SNRM profile, thus causing the SNRM dB down to be at 6ish dB upon resync. But as I've proven if I manually restart the modem, it syncs at 3dB.
I also thought DLM only took action several hours later, or during the next day. That's always been my previous experience when on the ECI cabinet. I've never seen it act so quickly, especially when sync on the line was never lost.
Am I correct in thinking if there was an event so bad that sync was lost entirely, the retrain reason would be zero? But it seems a stretch to think 70 mins after an SNRM dip, there would be another worse event which would cause sync to be lost entirely, and be ongoing during the modem retrain.