My understanding is that OASIS monitors the documents ECFMG received. ECFMG
scans the documents and then uploads them to ERAS PostOffice. Yes the
documents show up in ERAS PostOffice are already scanned by ECFMG.
From the instruction:
Applicant Document Tracking System (ADTS) Track the status of your ERAS
application materials using the Applicant Document Tracking System (ADTS) at http://services.aamc.org/eras/adts or click Track Applications under the Programs tab or the Account tab in MyERAS.
