^ is partially not good advice. If you’ve done your best and still end up with a D, do not notify the UCs until you’ve been accepted. The reason is, grades can change even after it has been posted, for any number of reasons. For example, at my kid’s HS, a grade will be changed to an A- in AP Bio/Chem/Physics if the person got a 5 and their grade was not an A. A student successfully appealed to the principal to get a grade changed because he was unfairly given a 0 on a huge group project in which one of the other members plagiarized his part of the paper.