It does irritate me when they are militant about deadlines but then don't bother to mark the work for absolutely ages.
For example, I had an assignment to hand in on the 15th December. My friend was ill so had an extension and handed hers in on the 15th January. When she gave it to the secretary, she saw the huge pile of completely unmarked essays behind her.... they hadn't even started! Frankly, we could have had the whole holidays to do that but instead, they made us hand them in at the end of the semester and we didn't get them back until late February.
Could this happen to you?