Just home after 6 sectors in virtually the exact same winds recorded during this tragedy, worse even if I'm honest, real handful and a strain on even a very senior training captain sitting on my left carrying out the toughest of the landings. But we never came within a million miles of leaving the runway, despite my best efforts.
Aside from the unusual Flap selection i think this is likely an EFATO gone wrong or potentially this could have happened:
Landed previous flight, forgot to retract flaps, rushed turn around, took off with Full Flap selected and rotated like a helicopter much earlier than expected and surprised the crew. Have had this done in training and if you are not expecting it is a BIG surprise.
Hopefully we find out.