That being said: g-d is outside the realm if time, that is why it says in Sefer Shemos, he is past, present & future. So Hashem is looking in from the outside to all the possibilities that you can ever make and knows the outcome of it. We are in a time-space dimension so it is hard for us to understand an existence not bound by time.
For us, we have the free-will to decide anything we want. As Feynman stated, there are multiple possibilities that can occur within time-space. However, the fact that Hashem is not bound by the dimension, he knows the outcomes of the past, present and future. SO if you do change your mind and the last second, your future also changes, and to hashem it is knows since time does not exist. All dimensions are one. I guess it comes down to Hamyvin Yovin.