Re the "triangle", I think the crack was due to the wind pulling the ice away from the coast, with the prevailing current pushing the ice back into place. But structurally it's not fast ice and could potentially be swept away.
Last year (or maybe the one before) I watched it through the whole summer, and most times it tends to drift back and forth, but sometimes when the movement over several days happens to be in one direction, a large piece may exit the shelter and be swept west into the Nares catchment area, or east past Kap Morris Jesup and bye bye through the Fram. It's mostly the luck of a random walk, plus sustained wind directions.
This year as it seems to be cracking earlier than normal, and with the Nares open since March instead of June, there is the potential of a lot of that triangle ice to be exported, which could make a difference for the melting season outcome.
For our resident expert animators, I suggest an animation over several months in 2018 (and other years?) zooming on this triangle and its immediate exits. It should be highly educational.
P.s. Having done some animations in the past, I know how time consuming it is so my heartfelt thanks for all the amazing stuff here and elsewhere.