When you place orders for stocks you can set the order to be automatically cancelled at the end of a chosen period if it is not filled in that period. That would be invaluable on PredictIt.
For example, you may perceive the probability of some event to be > x before you go to bed so you place a Yes order at x price. There may be some news before you wake up which drops the probability drastically below x so your order gets filled and you are stuck with junk Yes shares. With this feature you could have set the time in force to be until the end of the night so you don't sell your shares in the morning without be aware of the news.