I think so too sir, maybe as good as the rule added with the guess time limit sir!
example => date of guess date and time limit for guessing.
12-3-2019 when the contest starts
16-3-2019 contes closed at 23.00 for closing guesses.
The starting/ending times are already clearly stated in the terms though.
The deadline is every Thursday at 10 PM UTC time (also forum time).
Here is what is stated in the terms:
"The deadline to post your predictions is Thursday at 10 PM UTC time every week."
There are also other similar statements in the terms regarding the deadline.
As you can see, it is very clear and there is little room for misunderstanding. There is no need to state the start and end times, as you said, if the terms are already clearly stated.
This member waited approximately 1.5 hours before market close to update their prediction. There is nothing special about this. Anyone can wait until a little before market close and post a prediction like this. I had specifically reminded everyone last week in post #365 not to do this very thing. So clear terms don't work, bold red text doesn't work, and reminders do not work. So this is simply members showing a blatant disregard for terms. Nothing more!