Source:
How to Apply, the "Application updates" section, quoted below
"Significant experiential updates will be accepted after an applicant has been invited for an on-campus interview. No updates will be accepted prior to this time. These brief updates should be a paragraph or less within the text of an email to the Admissions Office. PDF updates and other attachments will not be processed.
We do not require or accept any updates to transcripts or grades. No materials should be mailed to the Admissions Office unless specifically requested. Applicants should not call the Admissions Office to check on application status."