Wind slab phantom

Noticed potential good snow and no tracks at the bottom of phantom couloir so we gave it a try, but the snow changed pretty quickly to firm wind slab as we we’re boot packing closer to the middle on the skiers right side. When we got to the middle, I then noticed a slab crown (see picture) . Seems like there wasn’t any sign of ski tracks above or bellow, so I assumed it was a natural release. Since we we’re a group of 3, we decided to turn around from there. Pretty hard to tell when that slab avalanche actually happened, but probably more than 24h ago.