Went to about 4900' up the enchanted trees skin track and dug a pit at 10:30 AM. Small 35° slope, S facing, semi tree sheltered. Top 6" F on top of 18" P to 1F (styrofoamy) followed by 4F. ECTP21, broke ~2' down at the old snow/new snow interface with energetic pop and crack shooting 3/4 across the block. Very clean shear.
It wasn't in an outrageously obvious location for wind loading and well hidden by new snow. Probably lots of these hiding around in less obvious locations. Another day to heal should help.