I am currently in the process of getting a fourth letter of recommendation. When it is finished, how should I send it out to schools? My options it seems are giving my recommender 18 stamped envelopes or doing it through AMCAS again. I'm not sure if AMCAS is for late recommendations after the primary is submitted though. Will AMCAS have to re-review parts of my app? Will that take forever and I'm better off with the envelopes?