OFAC's recent actions from 12 to 23 September 2026 list no Iran general licence extending or replacing General License DD, so the wind-down ended at 12.01am EDT on 23 September.
Hunch. Nothing has to be signed for the cut-off to happen, OFAC said on 10 September it would refuse most Iran licence requests, and the Treasury Secretary repeated the date two days before it.
The licence market resolves on the OFAC recent actions page and the Iran general licences list at ofac.treasury.gov: YES if no licence extending or replacing the 23 September wind-down in General License DD is issued before 12.01am EDT on 23 September 2026. The Federal Register API is the backup, and BBC News and Al Jazeera settle it if both official pages are unreachable.
Since 2018 we found eight US deadlines like this one. In each, the US government named a future date for a ban or limit on a country's planes or ships, in a published legal text. In seven, the ban started on the day named, with no delay, extension or withdrawal. Many cases come from Donald Trump's two terms. The one miss and the one later pause both came out of talks with China.