Delta has been in financial trouble for quite some time. The possible bankruptcy is getting closer due to the imminent decision of the pilots and their contract vote.
The last bankruptcy of a MAJOR airline was Eastern, many years ago, and I cannot recall what happened to purchased tickets.
Is there someone on the board who can give some input on what will happen to tickets already purchased, or soon to be purchased, based on past experiences? A Delta pilot, for example, or a friend of a pilot might be the knowledgeable source. I presume that the question of mileage awards would be an insignificant loss compared to the cost of tickets to overseas countries.