If you go back to that choice point exactly as it was -- with your beliefs, desires, and circumstances being exactly as they were originally -- then why think that you would have made a different choice? We can't make sense of your choosing differently unless we imagine that something is different about that choice point. One might claim that your original choice was indeterministic, so it could have been different even in exactly the same circumstances. But calling a choice "indeterministic" is just to say that, beyond a certain point, we can't make sense of it.
If you were to look back at a certain period (of time) that you did something, can you say with certainty (most likely) you would have done a different action instead of the action that you took that lead you to the present you. Or does it become another probability that you cannot infer that you would have most likely done things differently. Say for example you said that you would have most likely went to school B if you did not go to school A. Are you saying that if you went back to that instance in time, knowing all the stuff that you did you would most likely have chosen school B given your circumstances of you at the past without any of the future biases that you hold from choosing school A? Or does it become another possibility of a what if scenario where you cannot infer that you would have done this or that to certain degree? How can you say for certain you would have done that when you did not (choose school A) therefore there would be no certainty in what you would have done in the past?