All applicants who want to work in the U.S. while their AOS is being processed must acquire employment authorization unless they have been granted a non-immigrant status that does not end before the AOS is approved. If the applicant is self-employed, they must receive employment authorization.
Any employment authorization applicants generally take 60-90 days to be adjudicated. This timeframe may be longer than this norm if the applicant has an irregular or extensive history to review. Employment authorization can take no longer than a year, but is typically approved during the time it takes to complete the AOS approval. In some cases, the applicant may have to reapply for employment authorization if the AOS approval takes longer than a year. In order to prevent a lapse in employment, the foreigner should reapply in advance of expiring. If the foreigner is employed at any time without authorization it is a violation of immigration status and any adjustment of status is at risk.