Ok so it safe to assume the process bolded below from the help guide is automatic
"To designate additional schools once you have submitted your application to AMCAS, you must re-enter your AMCAS application, select the additional schools you wish to designate, and re-certify and re-submit your application to AMCAS. You must re-certify and re-submit your application with the additionally designated schools by the stated deadlines of the schools you wish to add. Deadlines may differ for different Program types."