my approval letter states that my enter and exit into Vietnam is from 10/10-10/11, but that is not the dates that I will be in Vietnam. Do I need to have the exact date printed on approval letter? or is this letter valid for the next month or so?
That means you are allowed to enter Vietnam anytime between 10 October and 10 November, though you do not need to enter Vietnam on exact 10 October, you will need to leave the country or use the letter of approval before the it runs expired on 10th November. hope it is now clear to you.