From experience... by removing and re-applying the same screen protector... all you're going to do is pick up more dust before re-applying. It's also almost impossible to get rid of dust that's stuck to the adhesive side of the screen protector.
You should just trash it and put a new one on. Good luck!
So not true. I've removed and reapplied a number of Steinheil films. Tape works well at getting the dust off.