Rules governing the tour length required in a Joint Duty Assignment List (JDAL) billet, and the appropriate joint tour credit, are dictated by Title 10, Section 664 as amended in the 2017 National Defense Authorization Act (NDAA). All orders to a JDAL tour are written for 36 months. An officer serving in a Standard Joint Duty Assignment (S-JDA) will be eligible for full joint duty credit upon departure if they've completed at least 22 months in an S-JDA billet. This policy does not change assignment tour length pursuant to DoDI 1315.18 or supersede Joint Travel Regulation requirements for assignments within or outside the continental United States.
Detailers are authorized to request the award of constructive credit be applied to an officer (other than a general or flag officer) who, for reasons of military necessity, is reassigned from an S-JDA within 60 days of meeting the 2-year joint tour length period. TRANSFERRING SO MUCH AS 24 HOURS EARLY IN THIS CASE CAN RESULT IN NO JOINT CREDIT!! If you fall into this category be sure to check with your detailer to confirm your check in (diary) date and that it's going to be possible for you to leave your billet.
Temporary duty periods of over 30 consecutive days away from an officer's assigned joint organization for Service-related duties, including pre-command or refresher training, or attendance at joint professional military education (JPME) courses, will not count toward the 24-month minimum for JDA credit.
Departures from an S-JDA to a command boarded position or developmental education before the minimum 22 months requires an OSD approved Joint Tour Length Waiver (JTLW) and would only grant accrued credit; any other early departure will typically result in no credit being awarded.