The AS9100D transition timeline is moving towards mandatory assessments to the 2016 revision. Much has occurred since fall 2016 including the AS9100-series standard release, auditor training, certification body approval, and, of course, organizational implementation.
All AS9100-series audits will be to the new AS9100-series starting in June 2017 to ensure full implementation by September 15, 2018, when the 2009 revision is retired. So why start the audits in June 2017? Transition to the 2016 revision will require a certification decision and therefore will require not only a transition audit with additional audit days, but also implementation and closure of any issued nonconformances, certification body verification, and technical review of all the associated documentation and audit reports to make a certification decision. The September 2018 date was selected to coincide with the ISO 9001:2015 transition schedules to keep organizations from having to transition first to the ISO 9001 and then to the AS9100D standard.