1) You dont get into medical school because your application is the first one completed; you get into medical school because your application is good.
2) The vast majority of medical schools require, recommend, or prefer committee letters (see AAMC Survey Summary of Medical School Letter Policies
https://aamc-orange.global.ssl.fast...d4e1d/msar_medical_school_letter_policies.pdf )
3) Application and candidate evaluations timeline varies widely by school may not done in a linear, chronological order. EDP, High achievers, URM, family of alumni, feeder schools, associated UG programs, linked postbaccs, and other factor may push an app forward in the process.
4) There are usually 3 main phases in processing application
----A) Initial Screening/Evaluation: A hybrid of automatic GPA/MCAT screen plus human for "quick review" of application. Used to for general priority and, in some cases, which team/subcommittee gets application. In some cases preset criteria can lead to II
----B)Full Evaluation: This is where evaluator/reader/team/subcommittee will fully evaluate all sections of primary, secondary, and LOR and generally summarize in broad categories or point system. This essentially becomes your priority for adcom review and II. This function may be split up among several evaluators and may go to a team or subcommittee for II decision
----C) Full adcom: this is where your fully evaluated application is reviewed and voted on by adcom for II on later on for acceptance/WL/rejection
5) Most adcoms dont start meeting for review of evaluated applicants until at least mid-August, more likely September, though some reviews may be done earlier for groups mentioned above. Evaluation may start almost immediately at schools.
6) Historically, the AMCAS application and overall admissions process is designed under the timeline that committee letters will not be written and arriving until after the beginning of the Fall term (ie September or later of application cycle). This is due to the deep-rooted "traditional" applicant model where 3rd year/junior students take Organic (now Biochem), MCAT, and apply in late Spring/early summer. Since grades from these courses as well as comments from the instructors were usually expected, and after the course is over many professors are gone for the summer and school functions slow down, it wasnt expected to get this info until the faculty returned in the Fall. Thus committee letters arent expected until at least the beginning of September