Wow! A good question! You are my hero!
Of course you can change it. The future is not set, and we do not know what the future will hold. Usually, what you are seeing is what will happen if a change is not made. Now, I wouldn't think that going into the vision astrally is going to change anything. try to determine what is the cause behind the circumstances in the vision and make a change.
As always, just my humble opinion,