Every department has their limitations on flexibility. It depends on which department you are in and if you are directly dealing with external parties. The management does their best to be flexible to suit each person's needs.
Very flexible. If you can work full time hours, you can get it. If you can only work tuesdays and wednesdays, you will only work tuesdays and wednesdays.
No. They are set, sometimes allocated as late as 6:00pm the evening before the required shift. 10 or 12 hour days.
No flex, set hours.