The calendar issue was resolved privately, but we can cunt-off about this totally Alderweireld-related maths problem if you like?
Unseen by you, I place a token under one of three cups and invite you to select which cup you think the token is under. Once you've chosen, I remove one of the other cups and show you it's empty.
There are now two cups in front of you: the one you originally chose and one other. You have the option to change if you want.
What should you do to have the best chance of finding the token: stick with your original choice or change? And what's the maths behind it?