The simple thing to do is write a letter to admissions, right now, just like you would have if you'd spotted this error last week, state your concerns, and include a copy of your latest transcript. (There's a fax number to send such letters to, or you can use old-fashioned snail-mail and use priority-mail delivery confirmation to be sure they get it.) I'm just a parent, not an admissions person, but I think it very unlikely that this change would shift your GPA significantly. And you will get some points for doing this promptly. In the extremely unlikely event they decided to institute some new policy to nail every kid for every single error, better to find out now, rather than in mid-July when they open your final transcript. I know a current Cal student who dropped an important class midway through the process...and made it through just fine...but he told Admissions about the change.