While BB has done pretty well in the task department this year, we still have not seen any 24-hour type tasks like we used to. There have been tasks that they could be called on at any time of day or night, but none where groups of HMs must be on the task in shifts all day and night.
That type of task is good because it tests stamina, as well as gets small groups or pairs of HMs to make conversation non-stop, and creates extra footage for Daily Shows.
In the past we have seen things like BB07's Counting Sheep task, BB07's Soccer task, BB06's Fishing Hole task, BB06's Water Tank task, BB05's Clock task, BB04's famous Orb task where Paul Dyer refused to stand under the watermelon-on-an-electromagnet and catch it if it falls, BB02's Bunker task, and many others that don't come to mind right now.
The Trainspotting task would have been a perfect candidate for this type of task. BB could have just gotten 2 HMs to be on the platform at all times, and sent trains around at all hours of the night, but instead he tells them when it is time for a train.