Planned and unplanned attempts but is turning the aircraft round and flying in the opposite direction for many hours until it ran out of fuel typical suicidal planning behaviour? I don't think it is.
I'm not sure there is such a thing as 'typical suicide planning behaviour'. From my own exposure to the subject, suicides can get themselves 'into position' and then take a long time to commit themselves to the final act. And I can imagine that letting the place run out of fuel and crash, in some ways might make it into an accident rather than suicide in a distorted mind.