US Customs continues to assess stakeholder readiness for the mandatory transition of post-release capabilities in ACE. In order to allow additional time for all stakeholders to prepare for this transition, and to provide the opportunity to solicit and receive public comment on the associated regulatory changes, CBP is rescheduling the October 29, 2016 transition.
This transition includes the mandatory use of ACE for liquidation, drawback, reconciliation, duty deferral, collections, statements, and the Automated Surety Interface. CBP is targeting January 2017 for the revised deployment and mandatory date and will provide additional clarification regarding the precise transition date in the coming weeks.
CBP official notice here.