Sympathetically triggered a long, slow running soft slab entering the notch today, attached is a photo taken from above. Propagation! Upon investigation, it became apparent that the bed surface contained intact buried stellar crystals, which are likely the culprit, though I'm not sure. I didn't dig. I didn't see any surface hoar or faceted grains. The avalanche did not seem to be wind related in nature. I also observed many dry loose point releases today, but none featuring a crown line, or apparent propagation. I'm not getting too excited, as I bet this instability is isolated and won't last.