You can't change reality in this meta-time sort of sense you seem to be eager to assign me. If I take a book out of the book case and put it on my desk I have changed the reality of where that book is. I haven't changed the reality of where that book will be in 2 minutes in your meta-time sense through my magical free will powers at the meta-time of making the decision to do that, but have changed the reality of where that book is in the plain English sense.

EDIT: You edited your post while I was replying. I only saw the first sentence.